taxonID	type	description	language	source
C436E549FF803263A8DBFA65FC8D7D0E.taxon	type_taxon	Type species. Travancoriana schirnerae Bott, 1969, by original designation; gender of genus feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF803263A8DBFA65FC8D7D0E.taxon	diagnosis	Diagnosis. Large sized crabs (maximum CW 55.3 mm). Carapace relatively broad (CW / CL = ca. 1.3 – 1.5), relatively low (CH / CW = ca. 0.4), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae well-developed, reaching lateral margins of carapace; external orbital angle broadly triangular, with long outer margin, ca. 4 times length of inner margin; epibranchial tooth low, located at same level of postorbital cristae; epistome posterior margin with well-developed, trapezoidal medial tooth and strongly sinuous lateral lobes (Fig. 2 A, B). Maxilliped 3 with well-developed flagellum on exopod (see Bahir & Yeo 2007: fig. 7 C). Chelipeds relatively stouter in adult males (Fig. 2 A). Ambulatory legs relatively stout, shorter, glabrous (Fig. 2 A). Male s 2 / s 3 visible as broad groove, not reaching edge of sternum; male s 3 / s 4 visible as shallow, complete groove, reaching edge of sternum (Fig. 2 C). Male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (Fig. 2 C). Male pleon relatively narrow, with strongly concave lateral margins; pleonal somite 6 subquadrate, relatively narrow, proximal width ca. 1.1 times medial length (Fig. 2 C). Male telson longer than broad, medial length ca. 1.2 times proximal width (Fig. 2 C). G 1 relatively slender; ultimate article conical, relatively slender, distally gently curved inwards, relatively short, ca. 0.3 – 0.4 times length of penultimate article; penultimate article moderately stout (Fig. 3 A, B). G 2 as long as G 1, ca. 1.0 times G 1 length; ultimate article long, ca. 0.5 – 0.6 times length of penultimate article (Fig. 3 C).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF803263A8DBFA65FC8D7D0E.taxon	discussion	Remarks. Bott (1969) established Travancoriana with a new species, Travancoriana schirnerae, as the type species. Subsequently, Bott (1970 b) included Paratelphusa (Barytelphusa) carli Roux, 1931, Paratelphusa (Barytelphusa) pollicaris Alcock, 1909, and Paratelphusa (Liotelphusa) malabarica Henderson, 1912, in Travancoriana. Paratelphusa (Liotelphusa) travancorica Henderson, 1913, was already added to the genus by Bott (1970 a). Bahir & Yeo (2007) revised Travancoriana and recognised five species (including Paratelphusa (Barytelphusa) pollicaris) in it, as they have assigned Paratelphusa (Barytelphusa) carli to Vela Bahir & Yeo, 2007, and Paratelphusa (Liotelphusa) malabarica and Paratelphusa (Liotelphusa) travancorica to Vanni. Pati & Sharma (2013) later described a new species of Travancoriana. Paratelphusa (Barytelphusa) napaea (Alcock, 1909) (originally in Potamon Savigny, 1816) was included in the checklist of Ng et al. (2008) without explanation. The generic position of Potamon napaeum Alcock, 1909, was recently clarified by Pati & Yeo (2022) who transferred it to Maydelliathelphusa Bott, 1969, instead. The following six species are thus known in Travancoriana s. lat.: T. charu Bahir & Yeo, 2007; T. convexa (Roux, 1931); T. granulata Pati & Sharma, 2013; T. kuleera Bahir & Yeo, 2007; T. pollicaris (Alcock, 1909); and T. schirnerae Bott, 1969 (type species) (Bahir & Yeo 2007; Pati & Sharma 2013). All the known species of Travancoriana s. lat. recognised by Bahir & Yeo (2007) and Pati & Sharma (2013) possess a distinctly transverse carapace, well-developed postorbital cristae, a broadly triangular external orbital angle with a long outer margin, and a long ultimate article of the G 1 (Figs. 2 A, 3 A, 4 A, B, E, F, 5 A, D, 6 A, F, 7 A, 8 A, 9 A, F, 10 A, 11 A, 12 A, B, E, H, 13 A). Travancoriana, however, is polyphyletic, with both T. charu and “ T. pollicaris ” [= Palaniana convexa (Roux, 1931) comb. nov.; see remarks below for Po. pollicaris (Alcock, 1909) comb. nov. and see remarks of Bahir & Yeo (2007) for T. convexa] forming separate clades from T. schirnerae in the phylogenetic tree of Klaus et al. (2014: fig. 1). Some species of Vanni also possess the diagnostic characters of Travancoriana sensu Bahir & Yeo (2007) (see remarks section for Vanni). It is, therefore, necessary to redefine the genus with additional generic suite of characters and also taking into consideration the geographical distribution of the congeners.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF8C3260A8DBFA40FC6B7F73.taxon	description	(Figs. 2, 3)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF8C3260A8DBFA40FC6B7F73.taxon	materials_examined	Type material. Holotype: male (CW 45.1 mm, CL 31.6 mm) (MHNG, uncatalogued), India, Tamil Nadu State, Nilgiris District, Coonoor, near Hillgrove, 11.338 ° N, 76.831 ° E, elev. 938 m a. s. l., coll. J. Carl, collection date unknown.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF8C3260A8DBFA40FC6B7F73.taxon	diagnosis	Diagnosis. As for genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF8C3260A8DBFA40FC6B7F73.taxon	discussion	Remarks. As mentioned by Bahir & Yeo (2007), T. schirnerae was described by Bott (1969, 1970 a, 1970 b) based on the specimens, which were earlier misidentified as Potamon (Potamonautes) cunicularis by Rathbun (1905) or as Paratelphusa (Barytelphusa) cunicularis by Alcock (1910) and Roux (1931). The records of the species from Karnataka, Kerala, and other districts of Tamil Nadu by Rathbun (1905), Alcock (1910), Srivastava (2005, 2007, 2013), Prabakar (2017), and Rajesh et al. (2017) are doubtful. Ecological notes. Travancoriana schirnerae can inhabit small, shallow, steep, rocky streams in shaded areas, with juveniles occurring within tea gardens (Bahir & Yeo 2007). Geographical distribution. As for genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF8C3260A8DBFA40FC6B7F73.taxon	description	Genus Ponmudiana gen. nov. (Figs. 4 – 6)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF8C3260A8DBFA40FC6B7F73.taxon	type_taxon	Type species. Travancoriana charu Bahir & Yeo, 2007, by present designation; gender of genus feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF8C3260A8DBFA40FC6B7F73.taxon	diagnosis	Diagnosis. Large sized crabs (maximum CW 52.1 mm). Carapace relatively broad (CW / CL = ca. 1.2 – 1.4), relatively low (CH / CW = ca. 0.4), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae well-developed, reaching lateral margins of carapace; external orbital angle broadly triangular, with long outer margin, ca. 5 times length of inner margin; epibranchial tooth low, located at same level of postorbital cristae; epistome posterior margin with well-developed, triangular medial tooth and concave lateral lobes (Figs. 4 A – C, E – G, 6 A, B). Maxilliped 3 with well-developed flagellum on exopod (Fig. 6 D). Chelipeds relatively stouter in adult males (Figs. 4 A, E, 6 A, C). Ambulatory legs relatively stout, shorter, glabrous (Figs. 4 A, E, 6 A, C). Male s 2 / s 3 visible as narrow, shallow groove, not reaching edge of sternum; male s 3 / s 4 only visible as 2 short lateral depressions (Figs. 4 D, H, 6 C). Male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (Figs. 4 D, H, 6 C). Male pleon relatively narrow, with concave lateral margins; pleonal somite 6 trapezoidal, relatively broad, proximal width ca. 1.3 times medial length (Figs. 4 D, H, 6 C, E). G 1 relatively slender; ultimate article conical or subcylindrical, relatively slender, relatively short, ca. 0.3 – 0.4 times length of penultimate article; penultimate article slender (Figs. 5 A, B, D, E, 6 F, G). G 2 slightly longer than G 1, ca. 1.1 times G 1 length; ultimate article long, ca. 0.5 – 0.6 times length of penultimate article (Figs. 5 C, F, 6 H). Vulvae relatively widely located from each other (VD / SW = ca. 0.2) (Fig. 6 I).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF8C3260A8DBFA40FC6B7F73.taxon	etymology	Etymology. The genus name is derived from the Ponmudi Hills of the southern Western Ghats of India, where the congeners live. The gender of this genus is feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF8C3260A8DBFA40FC6B7F73.taxon	discussion	Remarks. Ponmudiana gen. nov. is separated from Travancoriana s. str. and established for two species, viz., Po. charu (Bahir & Yeo, 2007) comb. nov. (type species herein designated) and Po. pollicaris (Alcock, 1909) comb. nov., based on the character states in male s 3 / s 4, male pleonal somite 6 and G 1 penultimate article (see Remarks for Travancoriana). Ponmudiana gen. nov. is unique among the gecarcinucid genera of southern India mainly due to its relatively low carapace (CH / CW = ca. 0.4) (Figs. 4 C, G, 6 B); the well-developed postorbital cristae reaching the lateral margins of the carapace (Figs. 4 A, B, E, F, 6 A); the broadly triangular external orbital angle with a long outer margin, ca. 5 times the length of the inner margin (Figs. 4 A, B, E, F, 6 A); the low epibranchial tooth located at the same level of the postorbital cristae (Figs. 4 A, B, E, F, 6 A); the well-developed flagellum on the exopod of the maxilliped 3 (Fig. 6 D); the male s 3 / s 4 only visible as two short lateral depressions (Figs. 4 D, H, 6 C); the relatively slender G 1 with a slender penultimate article (Figs. 5 A, B, D, E, 6 F, G); the slightly longer G 2 than the G 1 (Figs. 5, 6 F – H); and the relatively widely located vulvae (VD / SW = ca. 0.2) (Fig. 6 I). Geographical distribution. Ponmudiana gen. nov. is distributed in the southern Western Ghats of Kerala (Kollam and Thiruvananthapuram districts) and Tamil Nadu (Kanyakumari and Tirunelveli districts) of southern India (Bahir & Yeo 2007; Rajesh et al. 2017; present study) (Fig. 1 A).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF893267A8DBFA2BFB907B62.taxon	description	(Figs. 4 A – D, 5 A – C)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF893267A8DBFA2BFB907B62.taxon	materials_examined	Type material examined. Holotype: male (CW 40.4 mm, CL 30.7 mm) (ZRC 2003.0241), India, Kerala State, Thiruvananthapuram District, Ponmudi, 8.73861 ° N, 77.11936 ° E, elev. 339 m a. s. l., collector and collection date unknown. Other material examined. India – Tamil Nadu State: female (CW 28.7 mm, CL 21.7 mm, CH 11.2 mm, FW 8.0 mm) (ZSI-WRC C. 2164), Kanyakumari District, Kalakad Mundanthurai Tiger Reserve, Upper Kodayar Range, Muthukulivayal, 8.493 ° N, 77.380 ° E, elev. 1324 m a. s. l., coll. R. Babu et al., 23 August 2019; 2 males (CW 21.1 – 26.0 mm, CL 16.2 – 19.1 mm, CH 8.3 – 10.2 mm, FW 6.1 – 7.0 mm), female (CW 16.5 mm, CL 12.0 mm, CH 6.3 mm, FW 4.9 mm) (ZSI-WRC C. 2165), Kanyakumari District, Kalakad Mundanthurai Tiger Reserve, Upper Kodayar Range, Kanthapanai Odai, 8.538 ° N, 77.349 ° E, elev. 1292 m a. s. l., coll. R. Babu et al., 24 August 2019; female (CW 16.5 mm, CL 13.3 mm, CH 6.6 mm, FW 5.1 mm) (ZSI-WRC C. 2321), Tirunelveli District, Kalakad Mundanthurai Tiger Reserve, Ambasamudram Range, near Marapalam, 8.547 ° N, 77.375 ° E, elev. 1276 m a. s. l., coll. R. Babu et al., 25 August 2019.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF893267A8DBFA2BFB907B62.taxon	diagnosis	Diagnosis. Large sized crabs (maximum CW 40.4 mm). Carapace transversely broad (CW / CL = ca. 1.2 – 1.4) (Fig. 4 A, B); epigastric cristae slightly anterior to postorbital cristae (Fig. 4 A, B); male s 2 / s 3 visible as narrow, shallow groove, not reaching edge of sternum (Fig. 4 D); male telson relatively broad, medial length ca. 1.1 times proximal width, with concave lateral margins (Fig. 4 D); G 1 ultimate article conical, short, ca. 0.3 – 0.4 times length of penultimate article, with straight tip (Fig. 5 A, B); G 2 ultimate article long, ca. 0.5 – 0.6 times length of penultimate article (Fig. 5 C).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF893267A8DBFA2BFB907B62.taxon	discussion	Remarks. Ponmudiana charu comb. nov. can be distinguished from the only known congener, Po. pollicaris comb. nov., by the concave lateral margins of the male telson (Fig. 4 D) (versus male telson with almost straight lateral margins; Figs. 4 H, 6 C, E) and the conical G 1 ultimate article with a straight tip (Fig. 5 A, B) (versus G 1 ultimate article subcylindrical with a conspicuously bent tip; Figs. 5 D, E, 6 F, G). Ecological notes. Ponmudiana charu comb. nov. is known to dwell under boulders of streamlets in well shaded areas (Bahir & Yeo 2007). Geographical distribution. Ponmudiana charu comb. nov. is an endemic species of the southern Western Ghats in southern India and is known only from Kerala (Thiruvananthapuram district) and Tamil Nadu (Kanyakumari and Tirunelveli districts) (Bahir & Yeo 2007; Rajesh et al. 2017; present study) (Fig. 1 A).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	description	(Figs. 4 E – H, 5 D – F, 6)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	description	2022: 460 (list).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	materials_examined	Type material. Lectotype: male (CW 52.1 mm, CL 38.1 mm) (ZSIK 1779 – 87 / 10), south India, “ presented by Travancore Museum ”, collector and collection date unknown. Other material examined. India – Kerala State: 3 males (CW 43.1 – 47.1 mm, CL 32.1 – 36.2 mm, CH 18.3 – 20.6 mm, FW 10.5 – 11.5 mm), 2 females (CW 42.8 – 45.0 mm, CL 33.3 – 33.8 mm, CH 19.3 – 20.0 mm, FW 10.6 – 10.9 mm) (ZSI-WRC C. 1185), Thiruvananthapuram District, Ponmudi, 8.76556 ° N, 77.10972 ° E, elev. 945 m a. s. l., coll. V. U. Sheeja, 11 August 2014; male (CW 17.7 mm, CL 14.1 mm, CH 7.3 mm, FW 5.2 mm) (ZSI-WRC C. 1883), Thiruvananthapuram District, Seethakundu, near Ponmudi, 8.772 ° N, 77.108 ° E, elev. 1032 m a. s. l., coll. Md. Jafer Palot et al., 18 January 2019; 3 males (CW 19.4 – 28.2 mm, CL 14.8 – 21.8 mm, CH 8.3 – 11.9 mm, FW 5.5 – 7.9 mm) (ZSI-WRC C. 1878), Kollam District, Shendurney Wildlife Sanctuary, Pondimotta, 8.828 ° N, 77.217 ° E, elev. 1235 m a. s. l., coll. Md. Jafer Palot et al., 23 January 2019.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	diagnosis	Diagnosis. Large sized crabs (maximum CW 52.1 mm). Carapace transversely broad (CW / CL = ca. 1.3 – 1.4) (Figs. 4 E, F, 6 A); epigastric cristae in line with postorbital cristae (Figs. 4 E, F, 6 A); male s 2 / s 3 visible as broad groove, not reaching edge of sternum (Figs. 4 H, 6 C); male telson relatively narrow, medial length ca. 1.3 times proximal width, with almost straight lateral margins (Figs. 4 H, 6 C, E); G 1 ultimate article subcylindrical, short, ca. 0.4 times length of penultimate article, with conspicuously bent tip (Figs. 5 D, E, 6 F, G); G 2 ultimate article long, ca. 0.5 times length of penultimate article (Figs. 5 F, 6 H); vulvae subovate, large, occupying ca. 0.5 times length of s 6, located some distance from s 5 / s 6 (Fig. 6 I).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	discussion	Remarks. Ponmudiana pollicaris comb. nov. was described by Alcock (1909) as Paratelphusa (Barytelphusa) pollicaris from south India, probably from “ Travancore ” as it was presented by the Travancore Museum. Roux (1931) reported the species, with the same name, from the Anamalai Hills. Bott (1970 a, 1970 b) included the species in Travancoriana, with Paratelphusa (Barytelphusa) pollicaris convexa Roux, 1931, as a junior synonym. Bott (1970 a, 1970 b), however, did not examine the actual species as his figures (Bott 1970 b: pl. 4 figs. 42 – 44, pl. 26 fig. 21) were that of the Paratelphusa (Barytelphusa) pollicaris convexa, which Bahir & Yeo (2007) regarded as Travancoriana convexa. In addition to the figures of Bott (1970 b), the geographical origins (“ Anaimalais ” or “ Palnis ”) of the species, reported by Roux (1931) as Paratelphusa (Barytelphusa) pollicaris and by Bott (1970 a, 1970 b) and Klaus et al. (2014) as Travancoriana pollicaris, suggest that they were conspecific belonging to Travancoriana convexa. In this study, T. convexa is assigned to its own genus Palaniana gen. nov. (see remarks for Travancoriana). The assumption of Alcock (1909), that Po. pollicaris comb. nov. was supposed to be originated from “ Travancore ” [mostly covering southern Kerala of the present-day], is justified here with recent collections from Bonacaud and Ponmudi of the Thiruvananthapuram district, and the adjoining Shendurney Wildlife Sanctuary of the Kollam district (Rajesh et al. 2017; present study). The identity of T. pollicaris, reported in Srivastava (2007) from the Bannerghatta National Park of Karnataka and in Pati et al. (2014) from the Aralam and Parambikulam wildlife sanctuaries of northern / central Kerala, is uncertain as the species is unlikely to occur beyond southern Kerala. Ponmudiana pollicaris comb. nov. is differentiated from its lone congener, Ponmudiana charu comb. nov., mainly by the shapes of the male telson and G 1 ultimate article (see remarks for the latter species). Ecological notes. Ponmudiana pollicaris comb. nov. was reported by Rajesh et al. (2017) to be found under a boulder of a small stream. The present specimens were collected from elevations of 945 – 1235 m a. s. l.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	description	Geographical distribution. Ponmudiana pollicaris comb. nov. is precisely known from the southern Western Ghats of Kerala in Kollam and Thiruvananthapuram districts (Rajesh et al. 2017; present study) (Fig. 1 A).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	description	Genus Palaniana gen. nov. (Figs. 7 – 9)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	type_taxon	Type species. Paratelphusa (Barytelphusa) pollicaris convexa Roux, 1931, by present designation; gender of genus feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	diagnosis	Diagnosis. Large sized crabs (maximum CW 54.6 mm). Carapace relatively broad (CW / CL = ca. 1.2 – 1.4), relatively low (CH / CW = ca. 0.4), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae well-developed, reaching lateral margins of carapace; external orbital angle broadly triangular, with long outer margin, ca. 4 times length of inner margin; epibranchial tooth low, located at same level of postorbital cristae; epistome posterior margin with well-developed, triangular medial tooth and sinuous lateral lobes (Figs. 7 A, B, 9 A, B). Maxilliped 3 with well-developed flagellum on exopod (Fig. 9 D). Chelipeds relatively stouter in adult males (Figs. 7 A, 9 A, C). Ambulatory legs relatively stout, shorter, glabrous (Figs. 7 A, 9 A, C). Male s 2 / s 3 distinct as narrow groove, reaching edge of sternum; male s 3 / s 4 distinct as shallow, complete groove, reaching edge of sternum (Figs. 7 C, 9 C). Male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (Figs. 7 C, 9 C). Male pleon relatively broad, with almost straight lateral margins; pleonal somite 6 trapezoidal, relatively broad, proximal width ca. 1.5 times medial length (Figs. 7 C, 9 C, E). G 1 relatively stout; ultimate article conical, relatively stout, relatively long, ca. 0.5 – 0.6 times length of penultimate article; penultimate article stout (Figs. 8 A, B, 9 F, G). G 2 slightly longer than G 1, ca. 1.1 times G 1 length; ultimate article long, ca. 0.6 times length of penultimate article (Figs. 8 C, 9 H). Vulvae relatively widely located from each other (VD / SW = ca. 0.2) (Fig. 9 I).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	etymology	Etymology. The genus name is derived from the Palani Hills of the southern Western Ghats of India, which is the type locality of the type species. The gender of this genus is feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF88327BA8DBFCEDFCC9796A.taxon	discussion	Remarks. Palaniana gen. nov. is recognised here for a subspecies described by Roux (1931), i. e., Paratelphusa (Barytelphusa) pollicaris convexa, which was synonymised by Bott (1970 a, 1970 b) with T. pollicaris but reinstated by Bahir & Yeo (2007) as a distinct species, viz., T. convexa (also see remarks for Po. pollicaris comb. nov.). Palaniana gen. nov., with its only species Palaniana convexa (Roux, 1931) comb. nov., cannot be confused among the gecarcinucid genera of southern India because of the following suite of morphological features: the relatively low carapace (CH / CW = ca. 0.4) (Figs. 7 B, 9 B); the well-developed postorbital cristae reaching the lateral margins of the carapace (Figs. 7 A, 9 A); the broadly triangular external orbital angle, with a long outer margin, ca. 4 times the length of the inner margin (Figs. 7 A, 9 A); the low epibranchial tooth located at the same level of the postorbital cristae (Figs. 7 A, 9 A); the well-developed flagellum on the maxilliped 3 exopod (Fig. 9 D); the complete groove of the male s 3 / s 4 reaching the edge of the sternum (Figs. 7 C, 9 C); the broad male pleon, with almost straight lateral margins and the trapezoidal pleonal somite 6 (Figs. 7 C, 9 C, E); the relatively stout G 1 with the stout and long ultimate article, ca. 0.5 – 0.6 times the length of the penultimate article (Figs. 8 A, B, 9 F, G); the slightly longer G 2 as compared to the G 1 (Figs. 8, 9 F – H); and the relatively widely located vulvae (VD / SW = ca. 0.2) (Fig. 9 I). Geographical distribution. Palaniana gen. nov. is currently known from the southern Western Ghats of Kerala (Idukki, Palakkad, Pathanamthitta, and Thrissur districts) and Tamil Nadu (Coimbatore, Dindigul, and Theni districts), which are all contiguous areas of southern India (Roux 1931; Bott 1970 a, 1970 b; Bahir & Yeo 2007; Pati et al. 2014; Rajesh et al. 2017; present study) (Fig. 1 A).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF97327EA8DBFF1CFB737F5F.taxon	description	(Figs. 7 – 9)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF97327EA8DBFF1CFB737F5F.taxon	materials_examined	Type material. Lectotype: male (CW 51.2 mm, CL 37.8 mm) (MHNG, uncatalogued), India, Tamil Nadu State, Dindigul District, Palani, Thandikudi, 10.310 ° N, 77.643 ° E, elev. 1500 m a. s. l., coll. J. Carl, 26 April 1927. Other material examined. India – Kerala State: male (CW 25.2 mm, CL 19.2 mm, CH 10.3 mm, FW 7.8 mm) (ZSI-WGRC IR / INV / 9182), Idukki District, Munnar, Kadalar Shola, 10.1420 ° N, 77.0576 ° E, elev. 1738 m a. s. l., coll. K. G. Emiliyamma, 22 September 2014; 2 males (CW 12.7 – 27.7 mm, CL 9.1 – 20.8 mm, CH 5.0 – 11.7 mm, FW 4.3 – 7.7 mm), female (CW 29.2 mm, CL 21.5 mm, CH 11.8 mm, FW 8.0 mm) (ZSI-WRC C. 611), Idukki District, Eravikulam National Park, Meenathotti, gravel bank, 10.16049 ° N, 77.01072 ° E, elev. 1708 m a. s. l., coll. R. M. Sharma, 27 February 1995; 2 males (CW 17.5 – 23.2 mm, CL 13.5 – 18.2 mm, CH 7.5 – 9.8 mm, FW 5.2 – 6.4 mm), female (CW 21.4 mm, CL 16.7 mm, CH 8.9 mm, FW 6.2 mm) (ZSI-WRC C. 2361), Idukki District, Marayoor Forest Division, Nagamala Shola, 10.290 ° N, 77.135 ° E, elev. 1724 m a. s. l., coll. Md. Jafer Palot, 14 March 2023; 2 males (CW 15.5 – 22.3 mm, CL 12.0 – 17.3 mm, CH 6.3 – 9.5 mm, FW 4.9 – 6.8 mm) (ZSI-WGRC IR / INV / 9887), Palakkad District, Nelliyampathi, Thoothampara, 10.44920 ° N, 76.71545 ° E, elev. 693 m a. s. l., coll. K. G. Emiliyamma, 1 March 2017; male (CW 35.4 mm, CL 26.9 mm, CH 15.3 mm, FW 9.8 mm) (ZSI-WGRC IR / INV / 9892), Palakkad District, Nelliyampathi, Victoria, 10.47275 ° N, 76.68265 ° E, elev. 980 m a. s. l., coll. K. G. Emiliyamma, 27 February 2017; male (CW 16.5 mm, CL 13.2 mm, CH 7.0 mm, FW 5.2 mm), 3 females (CW 16.2 – 17.2 mm, CL 12.9 – 13.6 mm, CH 6.7 – 7.1 mm, FW 5.2 – 5.4 mm) (ZSI-WGRC IR / INV / 9890), Palakkad District, Nelliyampathi, Pothumala, 10.508 ° N, 76.683 ° E, elev. 977 m a. s. l., coll. K. G. Emiliyamma, 2 March 2017; male (CW 26.7 mm, CL 20.7 mm, CH 10.8 mm, FW 7.5 mm) (ZSI-WGRC IR / INV / 9153), Pathanamthitta District, Gavi, 9.43585 ° N, 77.16577 ° E, elev. 1190 m a. s. l., coll. P. M. Sureshan, 5 September 2015. – Tamil Nadu State: male (CW 14.1 mm, CL 11.0 mm, CH 5.4 mm, FW 4.2 mm), 3 females (CW 9.9 – 21.9 mm, CL 8.1 – 16.9 mm, CH 4.1 – 8.5 mm, FW 3.2 – 5.9 mm) (ZSI-WRC C. 2155), Theni District, Megamalai Wildlife Sanctuary, Upper Manalaru, 9.583 ° N, 77.335 ° E, elev. 1664 m a. s. l., coll. R. Venkitesan et al., 27 June 2019; male, juvenile (ZSI-WRC C. 2341), Theni District, Megamalai Wildlife Sanctuary, Chinnamannur Range, Upper Manalar, Vattaparai, 9.584 ° N, 77.331 ° E, elev. 1666 m a. s. l., coll. R. Babu et al., 4 March 2019; 2 females (CW 18.4 – 26.6 mm, CL 14.3 – 20.5 mm, CH 7.0 – 11.1 mm, FW 5.1 – 6.9 mm) (ZSI-WRC C. 2156), Theni District, Megamalai Wildlife Sanctuary, Vattaparai, 9.585 ° N, 77.331 ° E, elev. 1662 m a. s. l., coll. R. Venkitesan et al., 27 June 2019; male, juvenile (ZSI-WRC C. 2338), Theni District, Megamalai Wildlife Sanctuary, Upper Manalar, stream near Suruli Colony, 9.589 ° N, 77.342 ° E, elev. 1536 m a. s. l., coll. R. Babu et al., 17 September 2016; male (CW 38.7 mm, CL 28.4 mm, CH 15.3 mm, FW 10.0 mm) (ZSI-WRC C. 2157), Theni District, Megamalai Wildlife Sanctuary, Venniyaru Forest, 9.615 ° N, 77.330 ° E, elev. 1536 m a. s. l., coll. R. Venkitesan et al., 28 June 2019; 3 males (CW 8.5 – 20.9 mm, CL 7.0 – 15.8 mm, CH 3.3 – 8.0 mm, FW 2.9 – 6.3 mm) (ZSI-WRC C. 2340), Theni District, Megamalai Wildlife Sanctuary, Highwavys, shola forest near Forest Rest House, 9.638 ° N, 77.358 ° E, elev. 1540 m a. s. l., coll. R. Babu et al., 3 March 2019; 3 males (CW 21.7 – 26.5 mm, CL 17.4 – 20.6 mm, CH 8.6 – 10.9 mm, FW 6.1 – 7.5 mm), 2 females (CW 11.9 – 16.8 mm, CL 9.7 – 13.4 mm, CH 4.2 – 6.8 mm, FW 3.7 – 5.0 mm) (ZSI-WRC C. 2158), Theni District, Megamalai Wildlife Sanctuary, Mannoothu, Kadana Estate, 9.692 ° N, 77.401 ° E, elev. 1541 m a. s. l., coll. R. Venkitesan et al., 29 June 2019; 4 males, juveniles (ZSI-WRC C. 2339), Theni District, Megamalai Wildlife Sanctuary, stream near Kadana Estate, 9.698 ° N, 77.401 ° E, elev. 1453 m a. s. l., coll. R. Babu et al., 18 September 2016.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF97327EA8DBFF1CFB737F5F.taxon	diagnosis	Diagnosis. As for new genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF97327EA8DBFF1CFB737F5F.taxon	discussion	Remarks. Palaniana convexa comb. nov. was formerly reported as Paratelphusa (Barytelphusa) pollicaris by Roux (1931: 48) and as Travancoriana pollicaris by Bott (1970 a: 336; 1970 b: 41, pl. 4 figs. 42 – 44, pl. 26 fig. 21) and Klaus et al. (2014: table S 1), which is now regarded as Pa. convexa comb. nov. (see remarks for Po. pollicaris comb. nov.). The records of the species from the Kodagu district of Karnataka and Kollam district of Kerala by Pati et al. (2014) appear to be misidentification of the specimens; the remaining specimens examined by Pati et al. (2014), however, belong to Pa. convexa comb. nov. Ecological notes. Palaniana convexa comb. nov. is generally found in high mountains (elevation up to 1738 m a. s. l.) (Bahir & Yeo 2007; present study); it is also recorded from an elevation as low as 600 m a. s. l. (present study). The species is known to occupy small and shallow streams, especially underneath boulders, in addition to paddy fields and muddy canals (Bahir & Yeo 2007). Geographical distribution. As for new genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF97327EA8DBFF1CFB737F5F.taxon	description	Genus Anamudiana gen. nov. (Figs. 10, 11)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF97327EA8DBFF1CFB737F5F.taxon	type_taxon	Type species. Travancoriana granulata Pati & Sharma, 2013, by present designation; gender of genus feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF97327EA8DBFF1CFB737F5F.taxon	diagnosis	Diagnosis. Large sized crabs (maximum CW 44.4 mm). Carapace relatively broad (CW / CL = ca. 1.2 – 1.4), relatively low (CH / CW = ca. 0.3 – 0.4), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae well-developed, reaching lateral margins of carapace; external orbital angle broadly triangular, with long outer margin, ca. 4 times length of inner margin; epibranchial tooth low, located at same level of postorbital cristae; epistome posterior margin with well-developed, semicircular medial tooth and gently sinuous lateral lobes (Fig. 10 A, B). Maxilliped 3 with well-developed flagellum on exopod (Fig. 10 C). Chelipeds relatively slender in adult males (see Pati & Sharma 2013: figs. 2 A – C, 3 E). Ambulatory legs relatively stout, shorter, glabrous (Fig. 10 A; see Pati & Sharma 2013: fig. 2 A, C). Male s 2 / s 3 distinct as narrow groove, reaching edge of sternum; male s 3 / s 4 distinct as deep, complete groove, reaching edge of sternum (Fig. 10 D). Male sternopleonal cavity relatively shorter, reaching to imaginary line joining medial part of cheliped coxae (Fig. 10 D). Male pleon relatively narrow, with strongly concave lateral margins; pleonal somite 6 subquadrate, relatively broad, proximal width ca. 1.5 times medial length (Fig. 10 D, E). G 1 relatively slender; ultimate article conical, relatively slender, relatively short, ca. 0.25 times length of penultimate article; penultimate article moderately stout (Fig. 11 A, B). G 2 longer than G 1, ca. 1.2 times G 1 length; ultimate article long, ca. 0.4 times length of penultimate article (Fig. 10 C). Vulvae relatively widely located from each other (VD / SW = ca. 0.3) (Fig. 10 F).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF97327EA8DBFF1CFB737F5F.taxon	etymology	Etymology. Crabs of the new genus are found in the high mountains of the southern Western Ghats of India. The genus name is thus derived from Anamudi, the highest peak in the Western Ghats. The gender of this genus is feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF97327EA8DBFF1CFB737F5F.taxon	discussion	Remarks. Anamudiana gen. nov. comprises only one species, A. granulata (Pati & Sharma, 2013) comb. nov., which was described as T. granulata by Pati & Sharma (2013). The new genus can be differentiated from Travancoriana s. str. by the characters in the male chelipeds, male s 2 / s 3, male sternopleonal cavity, male pleonal somite 6, and G 1 ultimate article (see remarks for Travancoriana). From other gecarcinucid genera of southern India, Anamudiana gen. nov. can be distinguished by the following morphological characters: the relatively low carapace (CH / CW = ca. 0.3 – 0.4) (Fig. 10 B); the well-developed postorbital cristae reaching the lateral margins of the carapace (Fig. 10 A); the broadly triangular external orbital angle, with a long outer margin, ca. 4 times the length of the inner margin (Fig. 10 A); the low epibranchial tooth located at the same level of the postorbital cristae (Fig. 10 A); the well-developed flagellum on the exopod of the maxilliped 3 (Fig. 10 C); the deep, complete groove of the male s 3 / s 4 reaching the edge of the sternum (Fig. 10 D); the relatively shorter male sternopleonal cavity, reaching to the imaginary line joining the medial part of the cheliped coxae (Fig. 10 D); the relatively narrow male pleon, with the strongly concave lateral margins (Fig. 10 D, E); the subquadrate and relatively broad male pleonal somite 6 with proximal width ca. 1.5 times the medial length (Fig. 10 D, E); the relatively slender and short G 1 ultimate article, ca. 0.25 times the length of the penultimate article (Fig. 11 A, B); the relatively stouter G 1 penultimate article (Fig. 11 A, B); the longer G 2 as compared to the G 1 (Fig. 11); and the relatively widely located vulvae (VD / SW = ca. 0.3) (Fig. 10 F). Geographical distribution. Anamudiana gen. nov. is known only from the southern Western Ghats in the Idukki district of Kerala, southern India, where it is endemic (Pati & Sharma 2013) (Fig. 1 A).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	description	(Figs. 10, 11)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	materials_examined	Type material examined. Holotype: male (CW 33.7 mm, CL 26.1 mm, CH 15.0 mm, FW 10.3 mm) (ZSI-WRC C. 1132), India, Kerala State, Idukki District, Eravikulam National Park, Bheemanada, 10.19545 ° N, 77.08647 ° E, elev. 2209 m a. s. l., coll. K. C. Gopi et al., 12 April 1994. – Paratypes: male (CW 35.4 mm, CL 26.9 mm, CH 16.4 mm, FW 10.1 mm) (ZSI-WRC C. 579), same collection data as for holotype; 2 males (CW 14.1 – 32.4 mm, CL 11.0 – 23.9 mm, CH 5.7 – 13.3 mm, FW 4.9 – 9.7 mm), 3 females (CW 16.2 – 39.7 mm, CL 12.5 – 29.7 mm, CH 5.9 – 17.4 mm, FW 5.4 – 11.1 mm) (ZSI-WRC C. 572), India, Kerala State, Idukki District, Eravikulam National Park, Anamudi, 10.16969 ° N, 77.06400 ° E, elev. 2472 m a. s. l., coll. K. C. Gopi et al., 5 April 1994. Other material examined. India – Kerala State: male (CW 44.4 mm, CL 33.5 mm, CH 19.5 mm, FW 12.9 mm), female (CW 14.4 mm, CL 11.9 mm, CH 4.7 mm, FW 5.3 mm) (ZSI-WRC C. 598), Idukki District, Eravikulam National Park, Kolukkumalai, 10.05652 ° N, 77.21555 ° E, elev. 1725 m a. s. l., coll. M. S. Pradhan et al., 4 September 1993; female (CW 44.1 mm, CL 33.5 mm, CH 19.6 mm, FW 13.0 mm) (ZSI-WRC C. 584), same collection data as for preceding, coll. K. C. Gopi et al., 10 April 1994; male (CW 19.0 mm, CL 13.9 mm, CH 8.2 mm, FW 6.1 mm) (ZSI-WRC C. 574), Idukki District, Eravikulam National Park, Meenathotti, 10.16049 ° N, 77.01072 ° E, elev. 1708 m a. s. l., coll. K. C. Gopi et al., 6 April 1994; male (CW 22.2 mm, CL 16.3 mm, CH 9.0 mm, FW 7.0 mm), female (CW 16.1 mm, CL 11.9 mm, CH 6.4 mm, FW 5.1 mm) (ZSI-WRC C. 610), Idukki District, Eravikulam National Park, Anamudi, 10.16968 ° N, 77.06400 ° E, elev. 2472 m a. s. l., coll. R. M. Sharma, 28 February 1995; female (CW 21.2 mm, CL 15.6 mm, CH 8.5 mm, FW 6.7 mm) (ZSI-WRC C. 573), Idukki District, Eravikulam National Park, Rajamalai, 10.17366 ° N, 77.00903 ° E, elev. 2072 m a. s. l., coll. K. C. Gopi et al., 3 April 1994; male (CW 22.2 mm, CL 16.5 mm, CH 9.2 mm, FW 7.2 mm), female (CW 22.8 mm, CL 16.9 mm, CH 9.7 mm, FW 7.2 mm) (ZSI-WRC C. 575), same collection data as for preceding, 4 April 1994; male (CW 38.6 mm, CL 28.2 mm, CH 16.4 mm, FW 11.1 mm) (ZSI-WRC C. 635), Idukki District, Eravikulam National Park, Eravikulam Hut, 10.22164 ° N, 77.07854 ° E, elev. 2150 m a. s. l., coll. R. M. Sharma, 25 February 1995.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	diagnosis	Diagnosis. As for new genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	discussion	Remarks. The two high mountain dwellers, A. granulata comb. nov. and Pa. convexa comb. nov., share the same locality at Meenathotti of the Eravikulam National Park but might have different ecological requirements or habitat preferences. For instance, Pa. convexa comb. nov. was collected from the gravel bank of a fast-flowing stream at a relatively lower elevation (1708 m a. s. l.; see other material examined for Pa. convexa comb. nov.); while A. granulata comb. nov. generally prefers stagnant water bodies or slow-flowing streams at relatively higher elevations (1708 – 2472 m a. s. l.; see ecological notes below). Although both these above species can occupy the same general area and may have similar physiognomy (e. g., low carapace and broadly triangular external orbital angle with long outer margin; Figs. 7 A, 9 A, 10 A), A. granulata comb. nov. can be easily differentiated from Pa. convexa comb. nov., by the shallower cervical grooves (Fig. 10 A) (versus cervical grooves relatively deep; Figs. 7 A, 9 A); the semicircular medial tooth of the epistome posterior margin (Fig. 10 B) (versus epistome posterior margin with a triangular medial tooth; Figs. 7 B, 9 B); the relatively slender adult male chelipeds (see Pati & Sharma 2013: figs. 2 A – C, 3 E) (versus adult male chelipeds relatively stouter; Figs. 7 A, 9 A, C); the relatively shorter male sternopleonal cavity reaching to the imaginary line joining the medial part of the cheliped coxae (Fig. 10 D) (versus male sternopleonal cavity relatively longer reaching to the imaginary line joining the anterior part of the cheliped coxae; Figs. 7 C, 10 C); the relatively narrower male pleon with strongly concave lateral margins and a subquadrate pleonal somite 6 (Fig. 10 D, E) (versus male pleon relatively broader with almost straight lateral margins and a trapezoidal pleonal somite 6; Figs. 7 C, 9 C, E); and the relatively slender G 1, with a short ultimate article, ca. 0.25 times the length of the penultimate article (Fig. 11 A, B) (versus G 1 stout, with a long ultimate article, ca. 0.5 – 0.6 times the length of the penultimate article; Figs. 8 A, B, 9 F, G). Ecological notes. Anamudiana granulata comb. nov. is an inhabitant of the high-rolling plateau of the Eravikulam National Park, which is situated at an isolated mountain range of the southern Western Ghats (Pati & Sharma 2013). The highest peak of the Western Ghats, Anamudi (elevation 2690 m a. s. l.), is located within the national park. This species is known for occupying higher elevations of the Eravikulam National Park, including that at Anamudi (1708 – 2472 m a. s. l.). Crabs of this species were found in a small and swampy waterbody where small streams adjoin; individuals were also recorded from several streams within the national park (Pati & Sharma 2013). As opined by Pati & Sharma (2013), A. granulata comb. nov. might have evolved as a distinct species [now a distinct new genus] as it remains isolated and adapted for a unique ecosystem with higher elevations, shola forest, heavy rainfall during the monsoon and very low temperature during the winter.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	description	Geographical distribution. As for new genus. Genus Naduganiana gen. nov. (Figs. 12, 13)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	type_taxon	Type species. Travancoriana kuleera Bahir & Yeo, 2007, by present designation; gender of genus feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 28.0 mm). Carapace relatively broad (CW / CL = ca. 1.3 – 1.4), relatively low (CH / CW = ca. 0.4), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae well-developed, reaching lateral margins of carapace; external orbital angle broadly triangular, with long outer margin, ca. 3 times length of inner margin; epibranchial tooth low, located at same level of postorbital cristae; epistome posterior margin with well-developed, trapezoidal medial tooth and strongly sinuous lateral lobes (Fig. 12 A – C, E). Maxilliped 3 with well-developed flagellum on exopod (Fig. 12 F). Chelipeds relatively slender in adult males (Fig. 12 A). Ambulatory legs relatively stout, shorter, glabrous (Fig. 12 A, E). Male s 2 / s 3 distinct as broad, deep groove, not reaching edge of sternum; male s 3 / s 4 distinct as deep, complete groove, reaching edge of sternum (Fig. 12 D). Male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (Fig. 12 D). Male pleon relatively narrow, with strongly concave lateral margins; pleonal somite 6 subquadrate, relatively narrow, proximal width ca. 1.2 times medial length, with gently concave lateral margins (Fig. 12 D, G). Male telson as long as broad, medial length ca. 1.0 times proximal width, with gently concave lateral margins (Fig. 12 D, G). G 1 relatively stout; ultimate article conical, relatively slender, distally distinctly curved outwards, relatively short, ca. 0.4 times length of penultimate article, tip blunt and bent; penultimate article stout, with sinuous outer margin (Figs. 12 H, I, 13 A, B). G 2 longer than G 1, ca. 1.2 times G 1 length; ultimate article long, ca. 0.5 times length of penultimate article (Figs. 12 J, 13 C). Vulvae relatively widely located from each other (VD / SW = ca. 0.3) (Fig. 12 K).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	etymology	Etymology. The genus name is derived from the Nadugani Hills, which are located in the central Western Ghats of India bordering Kerala and Tamil Nadu states. The gender of this genus is feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	discussion	Remarks. The species described by Bahir & Yeo (2007) as Travancoriana kuleera is assigned to Naduganiana gen. nov. after comparing with Travancoriana s. str. (see remarks for Travancoriana). Naduganiana gen. nov. includes a lone species, Naduganiana kuleera (Bahir & Yeo, 2007) comb. nov. Naduganiana gen. nov. can be differentiated from the gecarcinucid genera of southern India by the following suite of morphological characters in addition to the medium sizes of the crabs (maximum CW 28.0 mm): the relatively low carapace (CH / CW = ca. 0.4) (Fig. 12 C); the well-developed postorbital cristae reaching the carapace lateral margins (Fig. 12 A, E); the broadly triangular external orbital angle, with the long outer margin, ca. 3 times the inner margin length (Fig. 12 A, E); the low epibranchial tooth located at the same level of the postorbital cristae (Fig. 12 A, E); the maxilliped 3 exopod with a well-developed flagellum (Fig. 12 F); the relatively deep male s 2 / s 3 and s 3 / s 4 with the latter suture distinct as a deep, complete groove, reaching the sternum edge (Fig. 12 D); the subquadrate and relatively narrow male pleonal somite 6, with the proximal width ca. 1.2 times the medial length (Fig. 12 D, G); the stout G 1 with a bent tip, the ultimate article being relatively slenderer and shorter, ca. 0.4 times the length of the penultimate article (Figs. 12 H, I, 13 A, B); the distinctly longer G 2 in relation to the G 1 length (Figs. 12 H – J, 13); and the relatively widely positioned vulvae (VD / SW = ca. 0.3) (Fig. 12 K). Naduganiana gen. nov. (see Figs. 12, 13) might be confused with Vanni (see Figs. 14 – 21) as did Pati et al. (2014, 2019 b) (see remarks for Naduganiana kuleera comb. nov.). This is mainly because of their subequal size, equally broad and low carapace, more or less equally long outer margin of the external orbital angle (ca. 2 – 3 times the length of the inner margin), and low epibranchial tooth (Figs. 12 A – C, E, 14 A, B, 16 A, B, 18 A – C, E, 20 A – C, E). Naduganiana gen. nov. is nevertheless separated from Vanni s. str. especially by the glabrous ambulatory legs (Fig. 12 A, E) (versus ambulatory legs setose; Figs. 14 A, 16 A, C, 18 A, E, 20 A, E), the distinct, deep, complete male s 3 / s 4 (Fig. 12 D) (versus male s 3 / s 4 indiscernible; Figs. 14 C, 16 C, G, 18 D, 20 D), and the relatively stouter G 1 with a bent tip and the relatively longer ultimate article, ca. 0.4 times the length of the penultimate article (Figs. 12 H, I, 13 A, B) (versus G 1 relatively slenderer with a straight tip and the relatively shorter ultimate article, ca. 0.2 – 0.3 times the length of the penultimate article; Figs. 15 A, B, 17 A, B, 18 H, I, 19 A, B, 20 H, I, 21 A, B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF923273A8DBFF1CFB5A7912.taxon	description	Geographical distribution. Naduganiana gen. nov. is restricted in distribution to the Nadugani Hills at the lower elevations (651 – 800 m a. s. l.) of the central Western Ghats, bordering Malappuram district of Kerala and Nilgiris district of Tamil Nadu, southern India (Bahir & Yeo 2007; present study) (Fig. 1 A).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9C3274A8DBFE3DFC167D0E.taxon	description	(Figs. 12, 13)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9C3274A8DBFE3DFC167D0E.taxon	materials_examined	Type material examined. Holotype: male (CW 28.0 mm, CL 19.7 mm) (ZRC 2003.0240), India, Kerala State, Malappuram District, “ between Gudalur and Manjery, Tamil Nadu ” [between Gudalur and Manjeri], 11.42536 ° N, 76.37961 ° E, elev. 800 m a. s. l., collector and collection date unknown. Other material examined. India – Tamil Nadu State: 3 males (CW 13.6 – 19.3 mm, CL 10.4 – 14.6 mm, CH 5.8 – 8.5 mm, FW 4.6 – 6.1 mm), 4 females (CW 11.4 – 19.3 mm, CL 8.9 – 14.5 mm, CH 4.7 – 8.4 mm, FW 3.8 – 5.9 mm) (ZSI-WRC C. 2470), Nilgiris District, Nilambur-Nadugani road, 11.438 ° N, 76.393 ° E, elev. 651 m a. s. l., coll. B. Tripathy et al., 24 November 2023.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9C3274A8DBFE3DFC167D0E.taxon	diagnosis	Diagnosis. As for new genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9C3274A8DBFE3DFC167D0E.taxon	discussion	Remarks. The records of the species as Travancoriana kuleera by Pati et al. (2014, 2019 b) from the Malabar Wildlife Sanctuary of the Kozhikode district of Kerala are a clear case of misidentification; the species appears like a species of Vanni instead (see Pati et al. 2014: pl. 1 figs. 13 – 15, pl. 3 figs. 10 – 12; 2019 b: pl. 1 fig. 4). The type locality of Naduganiana kuleera comb. nov. was stated as “ between Gudalur and Manjery, Tamil Nadu ” by Bahir & Yeo (2007). Based on the verbatim geographic coordinates provided by Bahir & Yeo (2007), Pati et al. (2014) confirmed that the holotype and male paratypes were originated from the Malappuram district of Kerala, while the female paratypes were from the Nilgiris district of Tamil Nadu. Some specimens of this species have also been collected from a stream that acts as a political boundary between Kerala and Tamil Nadu (see other material examined). The species is thus distributed in the Nadugani Hills on both sides of these two states. From the above-mentioned stream, crabs of Barytelphusa cunicularis (Westwood in Sykes, 1836) were also collected along with Na. kuleera comb. nov. (see ecological notes below). The subadult crabs (CW <44 mm) of B. cunicularis superficially resemble the adult crabs of Na. kuleera comb. nov. The male adults / subadults of B. cunicularis can be easily recognised from the male crabs of Na. kuleera comb. nov. (see remarks for Naduganiana gen. nov. on the differences among the new genus and other gecarcinucid genera of southern India). The female subadults of B. cunicularis, however, are likely to be confused with the females of Na. kuleera comb. nov., especially due to the presence of a more or less equally long outer margin of the external orbital angle (Fig. 12 A, E; see Pati & Yeo 2022: fig. 1 A). In such cases, the females of Na. kuleera comb. nov. can be differentiated from the subadult females of B. cunicularis by the following non-sexual characteristics: the epibranchial tooth is very low, almost indiscernible, and inseparable from the postorbital crista by the cervical groove (Fig. 12 A, E) (versus epibranchial tooth low but distinct, and separated from the postorbital crista by the deep cervical groove; see Pati & Yeo 2022: fig. 1 A); and the epistome posterior margin possesses a trapezoidal medial tooth, and the strongly sinuous lateral lobes (Fig. 12 C) (versus epistome posterior margin possessing a triangular medial tooth, and the concave lateral lobes with the outer parts sloping downwards; see Pati & Yeo 2022: fig. 1 B). Ecological notes. Naduganiana kuleera comb. nov. was reported by Bahir & Yeo (2007) to occur underneath small stones of a very shallow stream in a well-shaded area. The present specimens from the same general area were collected from under small stones and boulders of a stream in an open area. Two other gecarcinucid species, Barytelphusa cunicularis and Vela carli (Roux, 1931), were also found to inhabit the same and nearby streams.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9C3274A8DBFE3DFC167D0E.taxon	description	Geographical distribution. As for new genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9C3274A8DBFE3DFC167D0E.taxon	type_taxon	Type species. Paratelphusa (Liotelphusa) malabarica var. travancorica Henderson, 1913, by original designation; gender of genus feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9C3274A8DBFE3DFC167D0E.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 27.4 mm). Carapace relatively broad (CW / CL = ca. 1.2 – 1.4), relatively low (CH / CW = ca. 0.4 – 0.5), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae well-developed, reaching lateral margins of carapace; external orbital angle triangular, with short outer margin, ca. 2 – 2.5 times length of inner margin; epibranchial tooth indiscernible or low, located at same level of postorbital cristae; epistome posterior margin with well-developed, triangular medial tooth and gently sinuous lateral lobes (Figs. 14 A, B, 16 A, B, 18 A – C, E, 20 A – C, E). Maxilliped 3 with well-developed flagellum on exopod (Figs. 14 D, 16 E, 18 F, 20 F). Chelipeds relatively slender in adult males (Figs. 14 A, 16 A, C, F, 18 A, E, 20 A, E). Ambulatory legs relatively stout, shorter, setose (Figs. 14 A, 16 A, C, 18 A, E, 20 A, E). Male s 2 / s 3 visible as groove, not reaching edge of sternum; male s 3 / s 4 indiscernible (Figs. 14 C, 16 C, G, 18 D, 20 D). Male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (Figs. 14 C, 16 C, G, 18 D, 20 D). Male pleon relatively narrow, with strongly concave lateral margins; pleonal somite 6 subquadrate, relatively narrow, proximal width ca. 1.1 – 1.2 times medial length (Figs. 14 C, E, 16 C, H, 18 D, G, 20 D, G). G 1 relatively slender; ultimate article conical, relatively slender, relatively short, ca. 0.2 – 0.3 times length of penultimate article; penultimate article slender to moderately stout (Figs. 15 A, B, 17 A, B, 18 H, I, 19 A, B, 20 H, I, 21 A, B). G 2 longer than G 1, ca. 1.1 – 1.2 times G 1 length; ultimate article long, ca. 0.4 times length of penultimate article (Figs. 15 C, 17 C, 18 J, 19 C, 20 J, 21 C). Vulvae relatively widely located from each other (VD / SW = ca. 0.2) (Figs. 14 F, 16 J, 18 K, 20 K).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9C3274A8DBFE3DFC167D0E.taxon	discussion	Remarks. Vanni was recognised as a new genus by Bahir & Yeo (2007), who included seven species: V. ashini Bahir & Yeo, 2007; V. deepta Bahir & Yeo, 2007; V. giri Bahir & Yeo, 2007; V. malabarica (Henderson, 1912); V. nilgiriensis (Roux, 1931); V. pusilla (Roux, 1931); and V. travancorica (Henderson, 1913) (the type species). Vanni, however, is a polyphyletic genus, with V. nilgiriensis and V. malabarica forming separate clades from the clade comprising V. travancorica and V. deepta in the phylogenetic tree of Klaus et al. (2014: fig. 1). Morphologically, V. nilgiriensis and V. malabarica are also so distinct from Vanni s. str. (which includes the type species V. travancorica, as well as V. ashini, V. deepta, and a new species, V. gracilis sp. nov.) that each of these species requires new generic names as do V. giri and V. pusilla. The key identifying characters used by Bahir & Yeo (2007) to distinguish Vanni s. lat. from the other genera of southern India require amendment, especially since the genus is now known to be polyphyletic (Klaus et al. 2014). According to the identification key to the southern Indian freshwater crab genera provided by Bahir & Yeo (2007), Vanni possesses a set of key characters that includes a relatively squarish carapace, usually less strongly developed postorbital cristae, a less broad external orbital angle with a short outer margin (ca. 1.5 – 2 times the inner margin), and a proportionately shorter G 1 ultimate article (ca. 0.2 – 0.3 times the penultimate article), which differentiates it from Travancoriana that has a distinctly transverse carapace, usually strongly developed postorbital cristae, a distinctly broader external orbital angle with a long outer margin (ca. 3 – 5 times the inner margin), and a proportionately longer G 1 ultimate article (ca. 0.3 – 0.6 times the penultimate article). This set of key characters does not apply to all species of Vanni s. lat. For instance, the carapace is slightly to distinctly broad (CW / CL = ca. 1.2 – 1.4) in Vanni s. lat. (Figs. 14 A, 18 A, B, E, 20 A, B, E, 22 A, B, E, F, 23 A; see Bahir & Yeo 2007: figs. 32 A, 34 A, 36 A, 38 A, 40 A, 42 A, 44 A), which is comparable to that of Travancoriana s. lat. (CW / CL = ca. 1.2 – 1.4) (Figs. 2 A, 4 A, B, E, F, 6 A, 7 A, 9 A, 10 A, 12 A, B, E). The postorbital cristae are usually less strongly developed only in V. malabarica, V. nilgiriensis, and V. pusilla (Figs. 22 A, B, E, F, 23 A; see Bahir & Yeo 2007: figs. 34 A, 36 A, 38 A). The external orbital angle is broadly triangular with a long outer margin (ca. 3.5 – 5 times the inner margin) in V. pusilla, V. nilgiriensis, and V. giri (Figs. 22 A, B, E, F, 23 A; see Bahir & Yeo 2007: figs. 36 A, 38 A, 44 A). The ratios between the ultimate and penultimate articles of the G 1 in the species of Vanni s. lat. (0.2 – 0.4) (Figs. 15 A, 17 A, 18 H, 19 A, 20 H, 21 A, 24 A; see Bahir & Yeo 2007: figs. 35 C, 37 D, 43 A) overlap with those of Travancoriana s. lat. (0.25 – 0.4) (Figs. 3 A, 5 A, D, 6 F, 11 A, 12 H, 13 A) except for Travancoriana convexa (Figs. 8 A, 9 F). Vanni s. str. is thus redefined by the following combination of characters, which separates it from all other gecarcinucid genera of southern India: the carapace is relatively low (Figs. 14 B, 16 B, 18 C, 20 C); the postorbital cristae are well-developed, each reaching the lateral margins of the carapace (Figs. 14 A, 16 A, 18 A, B, E, 20 A, B, E); the external orbital angle is triangular, with a short outer margin, ca. 2 – 2.5 times the length of the inner margin (Figs. 14 A, 16 A, 18 A, B, E, 20 A, B, E); the epibranchial tooth is indiscernible or low (Figs. 14 A, 16 A, 18 A, B, E, 20 A, B, E); the maxilliped 3 possesses a distinct flagellum on the exopod (Figs. 14 D, 16 E, 18 F, 20 F); the ambulatory legs are relatively stout, shorter, setose (Figs. 14 A, 16 A, C, 18 A, E, 20 A, E); the male s 2 / s 3 is discernible as groove, while the male s 3 / s 4 is indiscernible (Figs. 14 C, 16 C, G, 18 D, 20 D); the male sternopleonal cavity is relatively short, reaching to the imaginary line joining the anterior part of the cheliped coxae (Figs. 14 C, 16 C, G, 18 D, 20 D); the G 2 is longer than G 1 (Figs. 15, 17, 18 H – J, 19, 20 H – J, 21); and the vulvae are relatively widely located from each other (VD / SW = ca. 0.2) (Figs. 14 F, 16 J, 18 K, 20 K).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9B324BA8DBFA40FEC77FB0.taxon	description	(Figs. 14, 15)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9B324BA8DBFA40FEC77FB0.taxon	materials_examined	Material examined. India – Kerala State: 7 males (CW 7.9 – 21.1 mm, CL 6.9 – 16.5 mm, CH 3.5 – 10.2 mm, FW 3.1 – 6.9 mm), 3 females (CW 10.5 – 11.7 mm, CL 8.7 – 9.9 mm, CH 5.2 – 5.6 mm, FW 4.0 – 4.2 mm) (ZSI-WRC C. 1877), Kollam District, Shendurney Wildlife Sanctuary, Pondimotta, 8.828 ° N, 77.217 ° E, elev. 1235 m a. s. l., coll. Md. Jafer Palot et al., 23 January 2019; 7 males (CW 13.9 – 22.0 mm, CL 10.9 – 16.3 mm, CH 6.6 – 10.0 mm, FW 5.1 – 7.3 mm), 5 females (CW 13.9 – 21.7 mm, CL 10.1 – 16.7 mm, CH 6.1 – 9.9 mm, FW 5.3 – 7.5 mm) (ZSI-WRC C. 1874), Kollam District, Shendurney Wildlife Sanctuary, Rockwood Estate, 8.870 ° N, 77.115 ° E, elev. 627 m a. s. l., coll. Md. Jafer Palot et al., 24 January 2019; 2 males (CW 12.9 mm each, CL 10.0 – 10.3 mm, CH 5.8 – 6.3 mm, FW 4.7 – 4.8 mm), 2 females (CW 9.2 – 13.5 mm, CL 7.4 – 10.9 mm, CH 4.3 – 6.6 mm, FW 3.6 – 5.0 mm) (ZSI-WRC C. 1888), Kollam District, Shendurney Wildlife Sanctuary, Kattilapara, 8.915 ° N, 77.110 ° E, elev. 190 m a. s. l., coll. Md. Jafer Palot et al., 21 January 2019; 2 males (CW 16.2 – 19.2 mm, CL 12.4 – 14.1 mm, CH 7.5 – 8.8 mm, FW 5.9 – 6.6 mm), 2 females (CW 17.9 – 18.0 mm, CL 13.5 – 13.7 mm, CH 8.1 – 8.6 mm, FW 6.2 mm each) (ZSI-WGRC IR / INV / 9143), Kollam District, Rosemala, 8.91845 ° N, 77.17440 ° E, elev. 355 m a. s. l., coll. K. Rajmohana, 18 December 2015; 4 males (CW 14.0 – 19.4 mm, CL 11.4 – 14.4 mm, CH 6.5 – 8.9 mm, FW 5.4 – 6.9 mm), 2 females (CW 14.7 – 15.4 mm, CL 11.8 – 12.3 mm, CH 6.6 – 7.4 mm, FW 5.7 mm each) (ZSI-WGRC IR / INV / 9146), Thiruvananthapuram District, Peppara Wildlife Sanctuary, Vayavanthol, 8.67452 ° N, 77.16330 ° E, elev. 340 m a. s. l., coll. K. Rajmohana, 14 December 2015; 3 males (CW 13.4 – 17.8 mm, CL 10.5 – 13.5 mm, CH 6.1 – 8.4 mm, FW 5.1 – 6.1 mm), female (CW 14.3 mm, CL 11.1 mm, CH 6.3 mm, FW 5.2 mm) (ZSI-WRC C. 1879), Thiruvananthapuram District, near Ponmudi, Seethakundu, 8.772 ° N, 77.108 ° E, elev. 1032 m a. s. l., coll. Md. Jafer Palot et al., 18 January 2019.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9B324BA8DBFA40FEC77FB0.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 22.6 mm). Carapace relatively broad (CW / CL = ca. 1.2 – 1.4), relatively low (CH / CW = ca. 0.4 – 0.5) (Fig. 14 A, B); external orbital angle triangular, with short outer margin, ca. 2.5 times length of inner margin (Fig. 14 A); epibranchial tooth indiscernible (Fig. 14 A); male sternopleonal cavity reaching to imaginary line joining anterior part of cheliped coxae (Fig. 14 C); male pleonal somite 6 subquadrate, relatively narrower, appearing elongated, proximal width ca. 1.1 times medial length, as long as telson, with strongly concave lateral margins (Fig. 14 C, E); male telson relatively more narrow, medial length ca. 1.3 times proximal width (Fig. 14 C, E); G 1 relatively stouter (Fig. 15 A, B); G 1 ultimate article relatively slenderer, straight, relatively shorter, ca. 0.2 times length of penultimate article (Fig. 15 A, B); G 1 penultimate article with distal portion conspicuously narrow than basal portion, outer margin gently sinuous, basally straight (Fig. 15 A, B); G 2 longer than G 1, ca. 1.2 times G 1 length, ultimate article long, ca. 0.4 times length of penultimate article (Fig. 15 C); vulvae subovate, relatively large, occupying ca. 0.5 times length of s 6, located clearly away from s 5 / s 6 (Fig. 14 F).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9B324BA8DBFA40FEC77FB0.taxon	discussion	Remarks. Vanni travancorica was described by Henderson (1913) as a new variety of Paratelphusa (Liotelphusa) malabarica. Roux (1931), however, recognised the variety as a distinct species, Paratelphusa (Barytelphusa) travancorica. Bott (1970 a) included the species in Travancoriana. Both Roux (1931) and Bott (1970 a) supposedly examined the specimens of Santanusus malabaricus (Henderson, 1912) comb. nov., not V. travancorica (see remarks for S. malabaricus comb. nov.). Bott (1970 b) changed his mind later and considered the species a junior subjective synonym of Travancoriana malabarica (Henderson, 1912). The figures in Bott (1970 b: pl. 5 figs. 45 – 47, pl. 26 fig. 22) suggest that the species was actually S. malabaricus comb. nov. (see remarks for S. malabaricus comb. nov.), while it also includes the male syntype of V. travancorica from the NHM. Subsequently, Bahir & Yeo (2007) removed the species from the synonym of Travancoriana malabarica and treated it as a valid taxon and the type species for their new genus, Vanni. Pati & Sharma (2011, 2014) erroneously reported the species from the Uttara Kannada district of Karnataka as evident from their figures (Pati & Sharma 2014: 30, fig. 6 A – G), and the fact that the said locality (Jog-Honnavar road) is far away (approximately 665 km) from the type locality of V. travancorica (i. e., Ponmudi); it is likely that their specimens belong to an unknown species of Vanni. Vanni travancorica is unique among known congeners in having a relatively more narrow male telson, with the medial length ca. 1.3 times the proximal width (Fig. 14 C, E) (versus male telson relatively less narrow, with the medial length ca. 1.0 – 1.1 times the proximal width; Figs. 16 C, H, 18 D, G, 20 D, G); in having a conspicuously narrow distal portion of the G 1 penultimate article as compared to its basal portion (Fig. 15 A, B) (versus G 1 penultimate article with the distal portion relatively less narrow than the basal portion; Figs. 17 A, B, 18 H, I, 19 A, B, 20 H, I, 21 A, B); and in having the vulvae located clearly away from the s 5 / s 6 (Fig. 14 F) (versus vulvae located relatively close to s 5 / s 6; Figs. 16 J, 18 K, 20 K). Vanni travancorica can be further distinguished from V. deepta and V. gracilis sp. nov. mainly by virtue of its relatively shorter G 1 ultimate article, ca. 0.2 times the length of the penultimate article (Fig. 15 A) (versus G 1 ultimate article relatively long, ca. 0.3 times the length of the penultimate article; Figs. 17 A, 18 H, 19 A) and by the basally straight outer margin of the G 1 penultimate article (Fig. 15 A, B) (versus G 1 penultimate article with the basally concave to strongly concave outer margin; Figs. 17 A, B, 18 H, I, 19 A, B); and from V. ashini by virtue of its indiscernible epibranchial tooth (Figs. 14 A) (versus epibranchial tooth low but discernible; Fig. 20 A, B, E) and by the relatively slenderer G 1 ultimate article (Fig. 15 A, B) (versus G 1 ultimate article relatively stouter; Figs. 20 H, I, 21 A, B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FF9B324BA8DBFA40FEC77FB0.taxon	description	Ecological notes. Vanni travancorica prefers to inhabit shady areas and was reported to dwell in shallow burrows in wet soil, underneath small stones and under leaf litters adjacent to small streams, and under stones and logs in wet soil (Bahir & Yeo 2007; Rajesh et al. 2017). The species was also reported to be very common at the type locality (Rajesh et al. 2017). The species can occupy both lower and higher elevations (100 – 1235 m a. s. l.) of the Western Ghats (cf. Bahir & Yeo 2007; present study). Geographical distribution. Vanni travancorica is currently found in the southern Western Ghats of Kerala (Kollam and Thiruvananthapuram districts), southern India (Bahir & Yeo 2007; Rajesh et al. 2017; present study) (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA7324DA8DBFF1CFE6C79DB.taxon	description	(Figs. 16, 17)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA7324DA8DBFF1CFE6C79DB.taxon	materials_examined	Type material examined. Holotype: male (CW 23.8 mm, CL 17.5 mm, CH 10.4 mm, FW 7.5 mm) (ZSI-WGRC IR / INV / 9192 A), India, Kerala State, Ernakulam District, Thattekkad Bird Sanctuary, Knachery, 10.12275 ° N, 76.74864 ° E, elev. 256 m a. s. l., coll. Md. Jafer Palot, 21 September 2016. – Paratypes: 2 males (CW 21.2 – 25.3 mm, CL 15.4 – 18.0 mm, CH 9.2 – 10.5 mm, FW 7.3 – 8.2 mm), female (CW 20.2 mm, CL 14.7 mm, CH 9.0 mm, FW 6.7 mm) (ZSI-WGRC IR / INV / 9192 B), same collection data as for holotype; 9 males (CW 13.9 – 21.2 mm, CL 10.7 – 15.9 mm, CH 5.6 – 9.2 mm, FW 5.0 – 7.4 mm), 7 females (CW 12.1 – 20.9 mm, CL 9.8 – 15.3 mm, CH 5.4 – 9.2 mm, FW 4.6 – 7.0 mm) (ZSI-WGRC IR / INV / 9192 C), same collection data as for holotype. Other material examined. India – Kerala State: 7 males (CW 12.7 – 21.5 mm, CL 10.2 – 15.6 mm, CH 6.0 – 9.7 mm, FW 4.9 – 7.4 mm), 10 females (CW 11.4 – 25.1 mm, CL 9.4 – 18.0 mm, CH 4.7 – 11.0 mm, FW 4.2 – 8.3 mm) (ZSI-WGRC IR / INV / 9159), Ernakulam District, Thattekkad Bird Sanctuary, Ovumkal, 10.11517 ° N, 76.70175 ° E, elev. 46 m a. s. l., coll. K. G. Emiliyamma, 27 October 2015; 3 males (CW 12.9 – 17.5 mm, CL 10.3 – 13.2 mm, CH 5.7 – 7.7 mm, FW 5.2 – 6.1 mm), 3 females (CW 15.7 – 23.5 mm, CL 12.1 – 16.7 mm, CH 6.9 – 9.8 mm, FW 5.7 – 8.1 mm) (ZSI-WGRC IR / INV / 9151), Ernakulam District, Thattekkad Bird Sanctuary, Kolumba, 10.11464 ° N, 76.70936 ° E, elev. 58 m a. s. l., coll. Md. Jafer Palot, 27 February 2014; 5 males (CW 14.7 – 20.0 mm, CL 11.3 – 14.9 mm, CH 6.4 – 9.0 mm, FW 5.4 – 6.9 mm), female (CW 24.5 mm, CL 17.4 mm, CH 10.7 mm, FW 8.0 mm) (ZSI-WGRC IR / INV / 9157), same collection data as for preceding, coll. P. M. Sureshan, 21 April 2015; 3 males (CW 19.3 – 19.4 mm, CL 14.2 – 14.5 mm, CH 8.2 – 9.1 mm, FW 6.8 – 7.3 mm), 2 females (CW 16.4 – 16.5 mm, CL 12.6 – 12.7 mm, CH 7.1 – 7.6 mm, FW 6.1 – 6.3 mm) (ZSI-WGRC IR / INV / 9187), same collection data as for preceding, coll. P. M. Sureshan, 18 June 2016; 6 males (CW 9.8 – 23.2 mm, CL 8.0 – 16.7 mm, CH 4.2 – 10.3 mm, FW 3.9 – 8.0 mm), 8 females (CW 12.2 – 23.8 mm, CL 9.4 – 16.9 mm, CH 5.1 – 10.3 mm, FW 4.6 – 8.3 mm) (ZSI-WGRC IR / INV / 9189), same collection data as for preceding, coll. Md. Jafer Palot, 20 September 2016; female (CW 20.1 mm, CL 15.2 mm, CH 9.0 mm, FW 7.0 mm) (ZSI-WGRC IR / INV / 9874), same collection data as for preceding, coll. K. Rajmohana, 5 February 2017; 8 males (CW 13.8 – 23.3 mm, CL 11.0 – 17.0 mm, CH 6.1 – 10.3 mm, FW 5.2 – 7.9 mm), female (CW 18.3 mm, CL 13.8 mm, CH 8.3 mm, FW 6.9 mm) (ZSI-WGRC IR / INV / 9148), Ernakulam District, Thattekkad Bird Sanctuary, Knachery, 10.12275 ° N, 76.74864 ° E, elev. 256 m a. s. l., coll. K. G. Emiliyamma, 29 October 2015; 3 males (CW 15.5 – 17.5 mm, CL 11.6 – 13.3 mm, CH 6.7 – 7.6 mm, FW 6.1 – 6.7 mm), 3 females (CW 12.7 – 18.6 mm, CL 9.8 – 14.0 mm, CH 5.0 – 8.8 mm, FW 5.0 – 7.1 mm) (ZSI-WGRC IR / INV / 9163), Ernakulam District, Thattekkad Bird Sanctuary, Urulanthanni, Pullasserykkuthu, 10.12594 ° N, 76.75106 ° E, elev. 81 m a. s. l., coll. K. G. Emiliyamma, 29 October 2015; male (CW 19.9 mm, CL 14.6 mm, CH 8.9 mm, FW 7.0 mm), female (CW 11.0 mm, CL 8.9 mm, CH 4.3 mm, FW 4.2 mm) (ZSI-WGRC IR / INV / 9175), Ernakulam District, Thattekkad Bird Sanctuary, Urulanthanni, 10.131 ° N, 76.750 ° E, elev. 120 m a. s. l., coll. Md. Jafer Palot, 25 February 2014; 2 females (CW 18.4 – 24.1 mm, CL 14.1 – 17.3 mm, CH 8.8 – 11.3 mm, FW 6.6 – 8.0 mm) (ZSI-WGRC IR / INV / 9155), same collection data as for preceding, coll. P. M. Sureshan, 22 April 2015; 2 males (CW 11.4 – 19.1 mm, CL 9.2 – 14.3 mm, CH 5.0 – 8.2 mm, FW 4.5 – 7.1 mm) (ZSI-WGRC IR / INV / 9878), same collection data as for preceding, coll. K. Rajmohana, 4 February 2017; 3 males (CW 15.7 – 17.8 mm, CL 12.2 – 13.4 mm, CH 6.8 – 8.0 mm, FW 5.9 – 6.5 mm), 4 females (CW 9.6 – 15.2 mm, CL 7.7 – 12.1 mm, CH 4.2 – 6.8 mm, FW 3.7 – 5.8 mm) (ZSI-WGRC IR / INV / 9173), Ernakulam District, Thattekkad Bird Sanctuary, between Urulanthanni-Thampakachodu, 10.1305 ° N, 76.7495 ° E, elev. 120 m a. s. l., coll. K. G. Emiliyamma, 6 January 2015; 2 males (CW 9.5 – 18.1 mm, CL 7.6 – 14.0 mm, CH 4.7 – 8.2 mm, FW 3.8 – 6.2 mm), 2 females (CW 15.5 – 16.1 mm, CL 12.1 – 12.6 mm, CH 6.8 – 7.1 mm, FW 5.5 – 5.7 mm) (ZSI-WGRC IR / INV / 9188), Ernakulam District, Thattekkad Bird Sanctuary, Kallippara, 10.13579 ° N, 76.72643 ° E, elev. 85 m a. s. l., coll. Md. Jafer Palot, 22 September 2016; 7 males (CW 9.7 – 20.8 mm, CL 7.7 – 15.8 mm, CH 4.3 – 9.7 mm, FW 3.9 – 7.5 mm), female (CW 15.2 mm, CL 11.6 mm, CH 6.7 mm, FW 5.5 mm) (ZSI-WGRC IR / INV / 9171), Ernakulam District, Thattekkad Bird Sanctuary, Koottampara, 10.1385 ° N, 76.73822 ° E, elev. 68 m a. s. l., coll. K. G. Emiliyamma, 28 October 2015; 2 males (CW 19.6 – 20.9 mm, CL 14.6 – 15.3 mm, CH 7.4 – 9.2 mm, FW 7.2 – 7.1 mm), 4 females (CW 15.3 – 18.5 mm, CL 11.7 – 13.7 mm, CH 6.7 – 8.7 mm, FW 5.8 – 6.4 mm) (ZSI-WGRC IR / INV / 9185), same collection data as for preceding, coll. P. M. Sureshan, 19 June 2016.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA7324DA8DBFF1CFE6C79DB.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 25.3 mm). Carapace relatively broad (CW / CL = ca. 1.2 – 1.4), relatively low (CH / CW = ca. 0.4 – 0.5) (Fig. 16 A, B); external orbital angle triangular, with short outer margin, ca. 2 times length of inner margin (Fig. 16 A); epibranchial tooth indiscernible (Fig. 16 A); male sternopleonal cavity reaching to imaginary line joining anterior part of cheliped coxae (Fig. 16 C, G); male pleonal somite 6 subquadrate, slightly broad, proximal width ca. 1.2 times medial length, as long as telson, with strongly concave lateral margins (Fig. 16 C, H); male telson relatively less narrow, medial length ca. 1.1 times proximal width (Fig. 16 C, H); G 1 relatively slenderer (Fig. 17 A, B); G 1 ultimate article relatively slenderer, gently curved outwards at ca. 10 ° from longitudinal axis of G 1, relatively longer, ca. 0.3 times length of penultimate article (Fig. 17 A, B); G 1 penultimate article with distal portion relatively less narrow than basal portion, outer margin sinuous, basally strongly concave (Fig. 17 A, B); G 2 slightly longer than G 1, ca. 1.1 times G 1 length, ultimate article long, ca. 0.4 times length of penultimate article (Fig. 17 C); vulvae subovate, relatively large, occupying ca. 0.6 times length of s 6, located relatively close to s 5 / s 6 (Fig. 16 J).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA7324DA8DBFF1CFE6C79DB.taxon	description	Description of male holotype. Medium sized crab (CW 23.8 mm). Carapace transversely subovate, broader than long (CW / CL = ca. 1.3), low (CH / CW = ca. 0.4); dorsal surface glabrous, generally smooth except for epigastric and postorbital cristae and lateral surfaces; anterolateral surface low in frontal view; anterolateral margins gently convex, subcristate, shorter than posterolateral margins; posterolateral margins converging posteriorly, strongly concave medially; front broad (FW / CW = ca. 0.3), deflexed anteriorly, trapezoidal, anterior margin cristate, smooth, gently concave medially in dorsal view; frontal medial triangle incomplete, with dorsal margin only, lateral margins indiscernible; epigastric cristae well-developed, rugose, slightly anterior to postorbital cristae; postorbital cristae well-developed, sharp, reaching lateral margins of carapace; external orbital angle triangular, with short outer margin, ca. 2 times length of inner margin; epibranchial tooth low, indiscernible; postorbital region concave; branchial regions low; cervical grooves shallow, broad, discontinuous, not reaching level of postorbital cristae; mesogastric groove deep, narrow, short, bifurcated posteriorly; H-shaped groove distinct; subhepatic region rugose, glabrous; suborbital region smooth, glabrous; pterygostomial region smooth, glabrous; supraorbital margin cristate, smooth; suborbital margin concave, cristate with low granules, discontinuous with supraorbital margin; epistome posterior margin with well-developed, triangular medial tooth and gently sinuous lateral lobes (Fig. 16 A – C). Eyes large; eyestalk short, moderately stout; cornea moderately large, pigmented (Fig. 16 B). Antennules long, folded in longitudinally broad fossae; antennae shorter than eyestalk (Fig. 16 B). Mandibular palp with 2 articles; terminal article bilobed, anterior lobe narrow, long, posterior lobe broad, short, ca. 0.5 times length of anterior lobe (Fig. 16 D). Maxillipeds 1, 2 each with long flagellum on exopod (Fig. 16 D). Maxilliped 3 cover most of buccal cavity, when closed; ischium subrectangular, longer than broad, longitudinal medial groove indiscernible; merus subrectangular, broader than long, anterolateral corner rounded; exopod slender, distally narrow, reaching proximal third length of ischium, with well-developed flagellum, exceeding merus width (Fig. 16 B, C, E). Chelipeds slender, smooth, glabrous, unequal, left chela larger (Fig. 16 A, C, F). Major chela with 2 distinct, blunt teeth on dactylus and 3 distinct, blunt, basally fused teeth on fixed finger, remaining teeth on fingers small, low, distinct gape when fingers closed; dactylus curved, moderately stout, longer than upper margin of palm, smooth; fixed finger stout, forming concave margin with ventral margin of palm; palm smooth, inflated, longer than high; carpus smooth, gently inflated, with prominent, broad, acute inner distal tooth and low, blunt basal tooth; merus smooth except for rugose or granular margins, lacking subterminal spine (Fig. 16 A, C, F). Ambulatory legs generally smooth, slender, long, P 3 longest; merus long, lacking subdistal spine; carpus setose; propodus and dactylus setose, with distinct, long, sharp chitinous spines on margins; dactylus (P 3, P 4) recurved, longer than propodus (Fig. 16 A, C). Thoracic sternites smooth, glabrous; s 1 and s 2 completely fused; s 2 / s 3 visible as very shallow groove, not reaching edge of sternum; s 3 / s 4 indiscernible; s 4 / s 5, s 5 / s 6, s 6 / s 7 shallow, narrow, medially interrupted; s 7 / s 8 shallow, narrow, medially interrupted by longitudinal groove of s 7, lacking transverse ridge; s 8 completely covered by pleon, narrowed medially, longitudinal medial groove distinct (Fig. 16 C, G). Pleonal locking mechanism with prominent tubercle on medial part of s 5 (Fig. 16 G). Sternopleonal cavity deep, short, reaching to imaginary line joining anterior part of cheliped coxae (Fig. 16 C, G). Pleon narrow, T-shaped, with strongly concave lateral margins; pleonal somites 1, 2 subrectangular, narrower than pleonal somite 3; pleonal somite 3 trapezoidal, broadest, with convex lateral margins; pleonal somites 4 and 5 trapezoidal, with straight and gently concave lateral margins, respectively; pleonal somite 6 subquadrate, slightly broader than long (proximal width ca. 1.2 times medial length), distinctly longer than preceding pleonal somites, subequal in length to telson, with strongly concave lateral margins (Fig. 16 C, H). Telson bell-shaped, slightly longer than broad (medial length ca. 1.1 times proximal width), with straight lateral margins, apex broad, rounded (Fig. 16 C, H). G 1 slender, short, tip reaching beyond s 6 / s 7 up to distal third of s 6 in situ; ultimate article conical, slender, short, ca. 0.3 times length of penultimate article, gently curved outwards at ca. 10 ° from longitudinal axis of G 1, tip blunt; penultimate article sinuous, slender, slightly broad at base, inner margin sinuous, outer margin sinuous, basally strongly concave; groove for G 2 marginal (Figs. 16 G, 17 A, B). G 2 slightly longer than G 1, ca. 1.1 times G 1 length; ultimate article long, ca. 0.4 times length of penultimate article, with acute tip; penultimate article stouter at proximal third (Fig. 17 C). Colour in life. The dorsal surface of the carapace is characterised by a mostly orange colour with dark purplish-brown blotches posteriorly; the chelipeds are entirely orange; and the ambulatory legs are light purplish-brown (https: // www. inaturalist. org / observations / 163961294).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA7324DA8DBFF1CFE6C79DB.taxon	etymology	Etymology. The species epithet is from the Latin word “ gracilis ”, meaning slender, which alludes to the fact that the slender male first gonopod of the species has the slenderest ultimate article among the known congeners. The species name is treated here as a Latin adjective in the nominative singular.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA7324DA8DBFF1CFE6C79DB.taxon	discussion	Remarks. The male paratypes of V. gracilis sp. nov., especially the adults, closely resemble the holotype in all diagnostic characters. The subadult male and female paratypes have a relatively less broad carapace (CW / CL = ca. 1.2 – 1.3). The female paratypes exhibit most of the non-sexual character states, similar to the holotype. In the adult females of V. gracilis sp. nov., the pleon and telson together form a broadly ovate outline and cover the thoracic sternum except for the lateral edges, when closed (Fig. 16 I). Their pleonal somite 1 is the shortest; pleonal somites 2 – 5 are progressively longer; and pleonal somite 6 is the longest, conspicuously broader than long, subequal in length to the telson, with gently convex lateral margins (Fig. 16 I). Their female telson is broadly triangular, conspicuously broader than long, with almost straight lateral margins and broad apex (Fig. 16 I). The vulvae are widely located from each other (VD / SW = ca. 0.2) on the s 6; each vulva opens ventrally and is subovate, large, ca. 0.6 times the length of the s 6, located some distance from the s 5 / s 6, not touching the s 5 / s 6, surrounded by a low rim, and covered by a soft membranous operculum (Fig. 16 J).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA7324DA8DBFF1CFE6C79DB.taxon	description	Ecological notes. Vanni gracilis sp. nov. are found in degraded semi-evergreen forest patches of the Thattekkad Bird Sanctuary at lower elevations (46 – 256 m a. s. l.) of the southern Western Ghats. Crabs of this new species can be found underneath small boulders in moist areas and along stream banks. They are very abundant in the sanctuary. The new species was also found coexisting alongside either Karkata ghanarakta Pati, Rajesh, Raj, Sheeja, Kumar & Sureshan, 2017, or Pilarta punctatissima Pati, Rajesh, Raj, Sheeja, Kumar & Sureshan, 2017. Geographical distribution. Vanni gracilis sp. nov. is currently known only from the Thattekkad Bird Sanctuary in the Ernakulam district of Kerala, southern India (Fig. 1 B). The sanctuary is situated in the foothills of the southern Western Ghats (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA2324DA8DBFE75FB297FDF.taxon	description	(Figs. 18, 19)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA2324DA8DBFE75FB297FDF.taxon	materials_examined	Type material examined. Holotype: male (CW 17.8 mm, CL 12.8 mm) (ZRC 2003.0233), India, Kerala State, Idukki District, Kaduwappara, on Mundakayam-Kumily, 9.55722 ° N, 76.96111 ° E, elev. 685 m a. s. l., collector and collection date unknown. Other material examined. India – Kerala State: 7 males (CW 11.9 – 21.5 mm, CL 9.5 – 15.8 mm, CH 5.3 – 9.3 mm, FW 4.5 – 7.1 mm), 3 females (CW 12.7 – 15.4 mm, CL 10.1 – 12.0 mm, CH 5.8 – 7.0 mm, FW 4.7 – 5.6 mm) (ZSI-WRC C. 2108), Pathanamthitta District, Ranni Forest Division, Moozhiyar, 9.291 ° N, 77.132 ° E, elev. 1138 m a. s. l., coll. Md. Jafer Palot, 31 October 2021; 2 males (CW 15.9 – 17.2 mm, CL 12.3 – 12.8 mm, CH 7.1 – 7.4 mm, FW 5.4 – 5.9 mm) (ZSI-WRC C. 2169), Pathanamthitta District, Ranni Forest Division, Veluthode, 9.300 ° N, 77.040 ° E, elev. 155 m a. s. l., coll. K. A. Subramanian & R. Babu, 30 October 2021; male (CW 14.8 mm, CL 11.5 mm, CH 6.9 mm, FW 5.2 mm), female (CW 22.2 mm, CL 16.5 mm, CH 10.2 mm, FW 7.0 mm) (ZSI-WRC C. 2168), Pathanamthitta District, Ranni Forest Division, Pannikunnu, 9.318 ° N, 77.029 ° E, elev. 63 m a. s. l., coll. K. A. Subramanian & R. Babu, 30 October 2021.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA2324DA8DBFE75FB297FDF.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 22.2 mm). Carapace relatively broad (CW / CL = ca. 1.3 – 1.4), relatively low (CH / CW = ca. 0.4 – 0.5) (Fig. 18 A – C, E); external orbital angle triangular, with short outer margin, ca. 2 times length of inner margin (Fig. 18 A, B, E); epibranchial tooth indiscernible (Fig. 18 A, B, E); male sternopleonal cavity reaching to imaginary line joining anterior part of cheliped coxae (Fig. 18 D); male pleonal somite 6 subquadrate, slightly broad, proximal width ca. 1.2 times medial length, as long as telson, with gently concave lateral margins (Fig. 18 D, G); male telson relatively less narrow, medial length ca. 1.1 times proximal width (Fig. 18 D, G); G 1 relatively stouter (Figs. 18 H, I, 19 A, B); G 1 ultimate article relatively slenderer, straight, relatively longer, ca. 0.3 times length of penultimate article (Figs. 18 H, I, 19 A, B); G 1 penultimate article with distal portion relatively less narrow than basal portion, outer margin gently sinuous, basally concave (Figs. 18 H, I, 19 A, B); G 2 slightly longer than G 1, ca. 1.1 times G 1 length, ultimate article long, ca. 0.4 times length of penultimate article (Figs. 18 J, 19 C); vulvae subovate, relatively large, occupying ca. 0.5 times length of s 6, located relatively close to s 5 / s 6 (Fig. 18 K).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFA2324DA8DBFE75FB297FDF.taxon	discussion	Remarks. Vanni deepta can be differentiated from the known congeners by the gently concave lateral margins of the male pleonal somite 6 (Fig. 18 D, G) (versus male pleonal somite 6 with the strongly concave lateral margins; Figs. 14 C, E, 16 C, H, 20 D, G). This species can be also distinguished from the morphologically close V. gracilis sp. nov. mainly by the relatively stouter ultimate and penultimate articles of the G 1 (Figs. 18 H, I, 19 A, B) (versus G 1 ultimate and penultimate articles relatively slenderer; Fig. 17 A, B). Ecological notes. Vanni deepta is typically found inhabiting areas under stones and in moist soil, adjacent to streams (Bahir & Yeo 2007). The species can be found at lower as well as higher elevations (63 – 1138 m a. s. l.). Geographical distribution. Vanni deepta appears to be restricted to the southern Western Ghats in the Idukki and Pathanamthitta districts of Kerala, southern India (Bahir & Yeo 2007; present study) (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	description	(Figs. 20, 21)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	materials_examined	Type material examined. Holotype: male (CW 24.1 mm, CL 18.5 mm) (ZRC 2003.0232), India, Kerala State, Thiruvananthapuram District, Ponmudi, 8.76872 ° N, 77.11047 ° E, elev. 975 m a. s. l., collector and collection date unknown. Other material examined. India – Kerala State: female (CW 16.9 mm, CL 13.4 mm, CH 7.7 mm, FW 5.6 mm) (ZSI-WGRC IR / INV / 9158), Thiruvananthapuram District, Bonacaud, Pandipath, 8.68071 ° N, 77.16733 ° E, elev. 547 m a. s. l., coll. K. Rajmohana, 15 December 2015. – Tamil Nadu State: male (CW 16.5 mm, CL 12.9 mm, CH 7.3 mm, FW 5.4 mm), female (CW 15.3 mm, CL 12.0 mm, CH 6.8 mm, FW 5.1 mm) (ZSI-WRC C. 2322), Kanyakumari District, Kalakad Mundanthurai Tiger Reserve, way to Muthukulivayal II Bend, 8.476 ° N, 77.383 ° E, elev. 994 m a. s. l., coll. Varadaraju, 16 February 2020; female (CW 23.0 mm, CL 16.7 mm, CH 10.3 mm, FW 6.6 mm) (ZSI-WRC C. 2323), Tirunelveli District, Kalakad Mundanthurai Tiger Reserve, Kalakad Range, Sengaltheri, Tiger Cave, 8.523 ° N, 77.447 ° E, elev. 1170 m a. s. l., coll. R. Babu et al., 15 March 2022; male (CW 16.4 mm, CL 12.3 mm, CH 6.9 mm, FW 5.1 mm), 3 females (CW 21.0 – 27.4 mm, CL 15.2 – 19.9 mm, CH 9.0 – 11.8 mm, FW 6.1 – 7.9 mm) (ZSI-WRC C. 2166), Tirunelveli District, Kalakad Mundanthurai Tiger Reserve, Kalakad Range, Shengaltheri, Karumandi Amman Kovil, Manimuthar River, 8.530 ° N, 77.446 ° E, elev. 983 m a. s. l., coll. R. Babu et al., 14 August 2019; 2 males (CW 19.4 – 23.6 mm, CL 14.3 – 17.0 mm, CH 8.3 – 9.7 mm, FW 5.7 – 6.9 mm), 5 females (CW 22.7 – 26.6 mm, CL 16.7 – 18.9 mm, CH 9.7 – 11.1 mm, FW 6.6 – 7.5 mm) (ZSI-WRC C. 2324), Tirunelveli District, Kalakad Mundanthurai Tiger Reserve, Kalakad Range, Sengalteri, Kulirati, 8.531 ° N, 77.456 ° E, elev. 962 m a. s. l., coll. R. Babu et al., 16 March 2022; male (CW 14.3 mm, CL 11.2 mm, CH 6.5 mm, FW 4.8 mm) (ZSI-WRC C. 2167), Tirunelveli District, Kalakad Mundanthurai Tiger Reserve, Ambasamudram Range, Marapalam, 8.544 ° N, 77.375 ° E, elev. 1169 m a. s. l., coll. R. Babu et al., 21 August 2019.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 27.4 mm). Carapace relatively broad (CW / CL = ca. 1.3 – 1.4), relatively low (CH / CW = ca. 0.4 – 0.5) (Fig. 20 A – C, E); external orbital angle triangular, with short outer margin, ca. 2 times length of inner margin (Fig. 20 A, B, E); epibranchial tooth low, discernible (Fig. 20 A, B, E); male sternopleonal cavity reaching to imaginary line joining submedial part of cheliped coxae (Fig. 20 D); male pleonal somite 6 subquadrate, slightly broad, proximal width ca. 1.1 times medial length, longer than telson, with strongly concave lateral margins (Fig. 20 D, G); male telson as long as broad, medial length ca. 1.0 times proximal width (Fig. 20 D, G); G 1 relatively stouter (Figs. 20 H, I, 21 A, B); G 1 ultimate article relatively stouter, gently curved outwards at ca. 10 ° from longitudinal axis of G 1, relatively shorter, ca. 0.2 times length of penultimate article (Figs. 20 H, I, 21 A, B); G 1 penultimate article with distal portion relatively less narrow than basal portion, outer margin gently sinuous (Figs. 20 H, I, 21 A, B); G 2 longer than G 1, ca. 1.2 times G 1 length, ultimate article long, ca. 0.4 times length of penultimate article (Figs. 20 J, 21 C); vulvae subovate, relatively large, occupying ca. 0.6 times length of s 6, located relatively close to s 5 / s 6 (Fig. 20 K).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	discussion	Remarks. Vanni ashini was reported by Pati et al. (2014) at a lower elevation (118 m a. s. l.) of the central Western Ghats, north of the Palghat Gap, in the Palakkad district of Kerala, which is an erroneous record as evident from their figures (Pati et al. 2014: pl. 2 figs. 7 – 9, pl. 4 figs. 3 – 5). Its occurrence there is highly unlikely as the species lives at the relatively higher elevations of the southern Western Ghats (see ecological notes and geographic distribution below). Vanni ashini can be distinguished from the other species of the same genus by the low but distinct epibranchial tooth (Fig. 20 A, B, E) (versus epibranchial tooth indiscernible; Figs. 14 A, 16 A, 18 A, B, E); the longer male pleonal somite 6 as compared to telson length (Fig. 20 D, G) (versus male pleonal somite 6 as long as telson; Figs. 14 C, E, 16 C, H, 18 D, G); the male telson being equally long as broad, the medial length ca. 1.0 time the proximal width (Fig. 20 D, G) (versus male telson longer than broad, the medial length ca. 1.1 – 1.3 time the proximal width; Figs. 14 C, E, 16 C, H, 18 D, G); and the relatively stouter G 1 ultimate article (Figs. 20 H, I, 21 A, B) (versus G 1 ultimate article relatively slenderer; Figs. 15 A, B, 17 A, B, 18 H, I, 19 A, B). Ecological notes. Vanni ashini inhabits shady and dry stream margins underneath stones in moist soil (Bahir & Yeo 2007). The recent specimens were collected from drying to shallow and slow-flowing streams at relatively higher elevations (547 – 1170 m a. s. l.) of the southern Western Ghats.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	description	Geographical distribution. Vanni ashini is endemic to the southernWestern Ghats of Kerala (Thiruvananthapuram district) and Tamil Nadu (Kanyakumari and Tirunelveli districts) in southern India (Bahir & Yeo 2007; Rajesh et al. 2017; present study) (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	description	– Male pleonal somite 6 with strongly concave lateral margins (Fig. 16 C, H); G 1 relatively slenderer, with relatively slenderer ultimate and penultimate articles (Fig. 17 A, B) ............................................ Vanni gracilis sp. nov. [Kerala (Ernakulam district); southern Western Ghats only] Genus Santanusus gen. nov. (Figs. 22 – 24)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	type_taxon	Type species. Paratelphusa (Liotelphusa) malabarica Henderson, 1912, by present designation; gender of genus masculine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 21.6 mm). Carapace relatively broad (CW / CL = ca. 1.3 – 1.4), relatively low (CH / CW = ca. 0.4 – 0.5), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae weakly developed posterolaterally, not reaching lateral margins of carapace; external orbital angle triangular, with short outer margin, ca. 2.5 times length of inner margin; epibranchial tooth low, located at same level of postorbital cristae; epistome posterior margin with low, broadly triangular medial tooth and gently sinuous lateral lobes (Figs. 22 A – C, E – G, 23 A). Maxilliped 3 with well-developed flagellum on exopod. Chelipeds relatively slender in adult males (Figs. 22 A, E, 23 A). Ambulatory legs relatively stout, shorter, setose (Figs. 22 A, E, 23 A). Male s 2 / s 3 and s 3 / s 4 indiscernible (Fig. 22 D, H). Male sternopleonal cavity relatively long, reaching to imaginary line joining bases of maxilliped 3 (Fig. 22 D, H). Male pleon relatively narrow, with strongly concave lateral margins; pleonal somite 6 subquadrate, relatively narrow, proximal width ca. 0.9 times medial length (Fig. 22 H). G 1 relatively slender; ultimate article conical, relatively slender, relatively short, ca. 0.25 times length of penultimate article; penultimate article moderately stout (Fig. 24 A, B). G 2 as long as G 1, ca. 1.0 times G 1 length; ultimate article relatively short, ca. 0.3 times length of penultimate article (Fig. 24 C). Vulvae relatively widely located from each other (VD / SW = ca. 0.2) (Fig. 23 C).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	etymology	Etymology. The genus is named in honour of Santanu Mitra of the Crustacea Section of the Zoological Survey of India, Kolkata, for his contributions to the taxonomy of Indian freshwater crabs, in an arbitrary combination with the ending of Thelphusa Latreille, 1819. The gender of this genus is masculine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFAF3245A8DBFF1CFD147FF2.taxon	discussion	Remarks. Santanusus gen. nov. is differentiated from the morphologically most closely related Vanni s. str. (see Remarks for Vanni) and herein designated Paratelphusa (Liotelphusa) malabarica described by Henderson (1912) as the type species. This new genus thus contains only one species, i. e., S. malabaricus (Henderson, 1912) comb. nov. Santanusus gen. nov. is distinct from other freshwater crab genera of southern India in the following morphological features: the relatively low carapace (CH / CW = ca. 0.4 – 0.5) (Fig. 22 C, G); the weakly developed postorbital cristae, posterolaterally not reaching the carapace margin (Figs. 22 A, B, E, F, 23 A); the triangular external orbital angle, with outer margin short, ca. 2.5 times the inner margin length (Figs. 22 A, B, E, F, 23 A); the low epibranchial tooth (Figs. 22 A, B, E, F, 23 A); the low, broadly triangular medial tooth of the epistome posterior margin (Fig. 22 C, G); the well-developed flagellum on the maxilliped 3 exopod; the relatively stout and shorter ambulatory legs (Figs. 22 A, E, 23 A); the indiscernible male s 2 / s 3 and s 3 / s 4 (Fig. 22 D, H); the relatively long male sternopleonal cavity, reaching to the imaginary line joining the bases of the maxilliped 3 (Fig. 22 D, H); the relatively slender G 1, with the conical and short ultimate article, ca. 0.25 times the length of the penultimate article (Fig. 24 A, B); the equally long G 2 and G 1 (Fig. 24); the relatively shorter ultimate article of the G 2, ca. 0.3 times the length of the penultimate article (Fig. 24 C); and the relatively widely located vulvae (VD / SW = ca. 0.2) (Fig. 23 C). Geographical distribution. Santanusus gen. nov. is currently known from the central and southern Western Ghats of Kerala (Kozhikode, Palakkad, and Thrissur districts) and Tamil Nadu (Coimbatore district) of southern India (Henderson 1912; Roux 1931; Bott 1970 a, 1970 b; Bahir & Yeo 2007; Klaus et al. 2014; Pati et al. 2014, 2019 b; Rajesh et al. 2017; present study) (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB53258A8DBFF1CFD1A7D0E.taxon	description	(Figs. 22 – 24)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB53258A8DBFF1CFD1A7D0E.taxon	materials_examined	Type material. Lectotype: male (CW 13.6 mm, CL 10.1 mm) (NHM 1913.2.11.1), India, Kerala State, “ Cochin State Forest ” [Thrissur District, Cochin State Forest, stream near Kavalai], [ca. 10.387 ° N, 76.555 ° E], “ elev. ca. 305 m a. s. l. ”, presented by J. R. Henderson, “ October 2011 ”. Other type material examined. Paralectotypes: male (CW 18.0 mm, CL 13.2 mm, FW 6.9 mm, CH 8.3 mm), 2 females (CW 18.5 – 21.6 mm, CL 14.4 – 16.2 mm; smaller female FW 7.2 mm, CH 8.6 mm) (ZSIK 7936 / 10), same collection data as for lectotype, coll. J. R. Henderson. Other material examined. India – Kerala State: male (CW 14.4 mm, CL 10.9 mm, CH 6.6 mm, FW 5.4 mm) (ZSI-WGRC IR / INV / 10509), Kozhikode District, Kakkavayal, 11.493 ° N, 75.974 ° E, elev. 50 m a. s. l., coll. P. Girish Kumar, 8 January 2018.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB53258A8DBFF1CFD1A7D0E.taxon	diagnosis	Diagnosis. As for new genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB53258A8DBFF1CFD1A7D0E.taxon	discussion	Remarks. Henderson (1912) obtained nine males and eleven females and mentioned in the original publication that “ the type (Crustacea Reg. No. 7936 / 10) is preserved in the Indian Museum ”. Although he discussed the deposition of type specimens in the Indian Museum (= ZSIK), he did not specify their exact number. The present investigation, however, recovered only one male and two females as the types, with the catalogue number ZSIK 7936 / 10. The other two type specimens (male and female) were already presented to the NHM, likely by J. R. Henderson, and the male syntype (“ MLo 1913 - 2 - 11 - 1 - 2 ” [NHM 1913.2.11.1]) was listed by Bott (1970 b). The male syntype (NHM 1913.2.11.1) was designated as the lectotype by Bahir & Yeo (2007), which was supposedly examined by Bott (1970 b) as stated in Bahir & Yeo (2007). Bott (1970 b: pl. 5 figs. 45 – 47, pl. 26 fig. 22), however, illustrated a nontype male (from MHNG) of V. malabarica from the Aliyar River, Anamalai. In the species account, however, Bott (1970 b) cited “ MBa 798 a ” [NMB 798 a] for a specimen from the Aliyar River; he also cited a juvenile male (“ MBa 798 b ” [NMB 798 b]) from the Naduar River. These specimens of V. malabarica from Aliyar and / or Naduar rivers were previously identified by Roux (1931) as Paratelphusa (Barytelphusa) travancorica and by Bott (1970 a) as Travancoriana travancorica. The same juvenile male (NMB 798 b) from the Naduar River again appeared in the phylogenetic study of Klaus et al. (2014) under the name, Vanni malabarica. The specimens from the Aliyar and Naduar rivers and adjoining areas of the Coimbatore district of Tamil Nadu are those of S. malabaricus comb. nov., not V. travancorica. The type locality of S. malabaricus comb. nov. is the Cochin State Forest, and the types were collected from a stream near Kavalai, which was reported to be at an elevation of about 1000 feet (305 m a. s. l.) (see Henderson 1912). Pati et al. (2014) and Rajesh et al. (2017) mentioned that the type locality falls in “ Kochi ” [Ernakulam] and Palakkad districts, respectively. There was a tramway in the Cochin State Forest, which had been in operation during 1907 - 1963 between Parambikulam of Palakkad district and Chalakudy of Thrissur district, with Kavalai as a transitional location (Vimal Kumar 2019). The approximate geographic coordinates (10.387 ° N, 76.555 ° E) of the stream near Kavalai are now traced based on the elevation data provided by Henderson (1912). The stream near Kavalai actually falls in the Thrissur district of Kerala. Ecological notes. Santanusus malabaricus comb. nov. was found to be living underneath stones at the edge of a stream, preferring relatively dry zones, with few individuals actually observed in the water (Henderson 1912). Rajesh et al. (2017) reported that their collection of specimens included those found underneath the stones of a small stream, as well as larger individuals that inhabited the areas between plant roots along the banks of fast-flowing streams.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB53258A8DBFF1CFD1A7D0E.taxon	description	Geographical distribution. As for new genus. Genus Pusillosa gen. nov. (Figs. 25, 26)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB53258A8DBFF1CFD1A7D0E.taxon	type_taxon	Type species. Paratelphusa (Liotelphusa) pusilla Roux, 1931, by present designation; gender of genus feminine. Diagnosis. Small sized crabs (maximum CW 12.9 mm). Carapace relatively broad (CW / CL = ca. 1.2 – 1.4), relatively low (CH / CW = ca. 0.4), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae weakly developed posterolaterally, not reaching lateral margins of carapace; external orbital angle broadly triangular, with long outer margin, ca. 4 times length of inner margin; epibranchial tooth low, located at same level of postorbital cristae; epistome posterior margin with well-developed, triangular medial tooth and sinuous lateral lobes (Fig. 25 A – C; see Roux 1931: fig. 16; Bahir & Yeo 2007: figs. 37 A, 38 A, B). Maxilliped 3 with well-developed flagellum on exopod (Fig. 25 F). Chelipeds relatively slender in adult males (Fig. 25 A, G; see Roux 1931: fig. 16). Ambulatory legs relatively slender, longer, setose (Fig. 25 A, H; see Roux 1931: fig. 16). Male s 2 / s 3 and s 3 / s 4 indiscernible (Fig. 25 D; see Bahir & Yeo 2007: figs. 37 B, 38 C). Male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (Fig. 25 D; see Bahir & Yeo 2007: figs. 37 B, 38 C). Male pleon relatively broad, with strongly concave, rather angular lateral margins; pleonal somite 6 trapezoidal, relatively broad, proximal width ca. 1.5 times medial length (Fig. 25 D, I; see Roux 1931: fig. 17; Bahir & Yeo 2007: figs. 37 C, 38 C). G 1 relatively stout; ultimate article conical, relatively slender, relatively short, ca. 0.4 times length of penultimate article; penultimate article stout (Fig. 26 A, B; see Bahir & Yeo 2007: fig. 37 D, E). G 2 longer than G 1, ca. 1.2 times G 1 length; ultimate article long, ca. 0.4 times length of penultimate article (Fig. 26 C). Vulvae relatively widely located from each other (VD / SW = ca. 0.2) (Fig. 25 J).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB53258A8DBFF1CFD1A7D0E.taxon	etymology	Etymology. The genus name is an arbitrary combination of ‘ pusillus ’ (Latin for very small) and the genus name Thelphusa, which alludes to the very small size of the crabs. The gender of this genus is feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB53258A8DBFF1CFD1A7D0E.taxon	discussion	Remarks. Pusillosa gen. nov. can be set apart from Vanni s. str. by the very small size of the crabs and the characters in postorbital cristae, external orbital angle, ambulatory legs, male s 2 / s 3, male pleon, and G 1 (see Remarks for Vanni). This new genus currently includes the lone species, Pu. pusilla (Roux, 1931) comb. nov. Pusillosa gen. nov. can be recognised from the gecarcinucid genera of southern India mainly by the relatively low carapace (CH / CW = ca. 0.4), with moderately convex lateral margins (Fig. 25 A – C; see Roux 1931: fig. 16; Bahir & Yeo 2007: figs. 37 A, 38 A, B); the weakly developed postorbital cristae (Fig. 25 A, B; see Roux 1931: fig. 16; Bahir & Yeo 2007: figs. 37 A, 38 A); the broadly triangular external orbital angle, with outer margin long, ca. 4 times the inner margin length (Fig. 25 A, B; see Roux 1931: fig. 16; Bahir & Yeo 2007: figs. 37 A, 38 A); the low epibranchial tooth (Fig. 25 A, B; see Roux 1931: fig. 16; Bahir & Yeo 2007: figs. 37 A, 38 A); the distinct flagellum on the exopod of maxilliped 3 (Fig. 25 F); the relatively slender pereiopods, with the ambulatory legs being longer and setose (Fig. 25 A, G, H; see Roux 1931: fig. 16); the indiscernible male s 2 / s 3 and s 3 / s 4 (Fig. 25 D; see Bahir & Yeo 2007: figs. 37 B, 38 C); the strongly concave lateral margins of the male pleon, appearing rather angular (Fig. 25 D, I; see Roux 1931: fig. 17; Bahir & Yeo 2007: figs. 37 C, 38 C); the relatively stout G 1, with the conical and relatively short ultimate article (ca. 0.4 times the length of the penultimate article), and the relatively stouter penultimate article (Fig. 26 A, B; see Bahir & Yeo 2007: fig. 37 D, E); and the longer G 2 than G 1 (Fig. 26). Geographical distribution. Pusillosa gen. nov. is endemic to the central Western Ghats and known only from the higher elevations (2100 – 2315 m a. s. l.) of Nilgiris district in Tamil Nadu, southern India (Roux 1931; Bott 1970 a, 1970 b; Bahir & Yeo 2007; present study) (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	description	(Figs. 25, 26)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	materials_examined	Type material. Lectotype (designated herein based on illustrations of Bahir & Yeo (2007: figs. 37, 38 )): male (CW 12.0 mm, CL 8.4 mm) (NMB 801 a), India, Tamil Nadu State, Nilgiris District, Nilgiris, Avalanche, 11.315 ° N, 76.599 ° E, “ elev. 2100 m a. s. l. ”, coll. J. Carl, 18 January 1927. Other material examined. India – Tamil Nadu State: 4 males (CW 3.9 – 9.3 mm, CL 3.2 – 6.9 mm, CH 1.3 – 3.7 mm, FW 1.5 – 3.2 mm), 2 females (CW 8.2 – 8.3 mm, CL 6.4 – 6.5 mm, CH 3.3 – 3.4 mm, FW 3.1 mm each) (ZSI-WRC C. 2343), Nilgiris District, Nilgiris, Mukurthi Range, hill stream near earthen dam, 11.259 ° N, 76.526 ° E, elev. 2276 m a. s. l., coll. R. Babu et al., 14 February 2023; 4 males (CW 9.1 – 10.1 mm, CL 6.8 – 7.6 mm, CH 3.6 – 4.0 mm, FW 3.1 – 3.5 mm) (ZSI-WRC C. 2342), Nilgiris District, Nilgiris, on the way to Mukurthi Peak, Mukurthi Forest hill stream, 11.391 ° N, 76.518 ° E, elev. 2315 m a. s. l., coll. R. Babu et al., 12 February 2023.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	diagnosis	Diagnosis. As for new genus. Colour in life. The live colouration of the species was formerly not known. Pusillosa pusilla comb. nov. exhibits a deep purple colour of the carapace and pereiopods, with the ventral surface relatively paler and the chelipeds red-violet ventrally (https: // www. inaturalist. org / observations / 190552893).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	discussion	Remarks. Bott (1970 a, 1970 b) assigned Paratelphusa (Liotelphusa) pusilla Roux, 1931, to Gubernatoriana without any indications, because he had limited material. Roux (1931) originally examined four females and two males. Bott (1970 b) also mentioned the same number and gender of specimens, but one male and three females were from the MHNG without catalogue number, and one male and one female from the NMB with catalogue number NMB 801 a. Bott (1970 b) also designated the male from the MHNG as the lectotype (also see Bott 1970 a). On the contrary, he illustrated the male from NMB (Bott 1970 b: pl. 6, figs. 57 – 59) and mentioned it as the lectotype. The lectotype designation by Bott (1970 a, 1970 b) is, therefore, not clear. This discrepancy was also noted by Bahir & Yeo (2007) while assigning the species to Vanni, who specifically stated that Bott (1970 b) supposedly designated the NMB male specimen as the lectotype, and the MHNG male specimen appeared as the lectotype in the text due to a typographical error. Bahir & Yeo (2007), therefore, continued to provisionally regard the NMB male specimen as the paralectotype. Since Bott (1970 a, 1970 b) could not unambiguously select a particular syntype that acts as a unique name-bearing type as necessary according to Article 74.5 of the International Code of the Zoological Nomenclature (ICZN 1999), and Bahir & Yeo (2007) did not clearly identify a lectotype, the male specimen (12.0 × 8.4 mm) (NMB 801 a) illustrated by Bahir & Yeo (2007: figs. 37, 38) is hereby designated as the lectotype for the nomenclatural stability of Pusillosa pusilla (Roux, 1931) comb. nov. The present designation of the lectotype based on illustrations is code-compliant as per Article 74.4 (ICZN 1999). Pusillosa pusilla comb. nov. is likely to be confused with eye-catching, coloured small freshwater crabs, e. g., most species of Ghatiana Pati & Sharma, 2014, Gubernatoriana Bott, 1970, Inglethelphusa Bott, 1970, and Sahyadriana Pati & Thackeray, 2018. The species of Ghatiana, Gubernatoriana, Inglethelphusa, and Sahyadriana possess some morphological characters in common with those of Pu. pusilla comb. nov., for instance, the indiscernible or weakly developed postorbital cristae, the low epibranchial tooth, the setose ambulatory legs, and the indiscernible male s 2 / s 3 and s 3 / s 4 (cf. Pati & Thackeray 2018, 2021; Pati et al. 2022 b, 2023 c, 2024). These morphological similarities could have confused Bott (1970 a, 1970 b) in assigning the species to Gubernatoriana. Pusillosa pusilla comb. nov. need not be confused with any of the species of Ghatiana, Gubernatoriana, Inglethelphusa, and Sahyadriana because it possesses the well-developed flagellum on the maxilliped 3 exopod (Fig. 25 F) (versus maxilliped 3 exopod completely lacking a flagellum; see Pati & Thackeray 2018, 2021; Pati et al. 2022 b, 2023 c, 2024), and the distinctly longer G 2, ca. 1.2 times the G 1 length, with a long ultimate article, ca. 0.4 times the length of the penultimate article (Fig. 26) (versus G 2 and its ultimate article conspicuously short; Pati & Thackeray 2018, 2021; Pati et al. 2022 b, 2023 c, 2024). Ecological notes. Pusillosa pusilla comb. nov. is a high mountain dweller, living at elevations of 2100 – 2315 m a. s. l. (Roux 1931; present study). The recent specimens were collected underneath small stones at the margins of shallow and slow-flowing streams and adjacent areas.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	description	Geographical distribution. As for new genus. Genus Nilgiriana gen. nov. (Figs. 27 – 29, 30 A)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	type_taxon	Type species. Paratelphusa (Liotelphusa) nilgiriensis Roux, 1931, by present designation; gender of genus feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 24.7 mm). Carapace relatively broad (CW / CL = ca. 1.3 – 1.5), relatively low (CH / CW = ca. 0.4), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae weakly developed posterolaterally, not reaching lateral margins of carapace; external orbital angle broadly triangular, with long outer margin, ca. 4 – 5 times length of inner margin; epibranchial tooth low, located at same level of postorbital cristae; epistome posterior margin with well-developed, triangular medial tooth and gently to strongly sinuous lateral lobes (Figs. 27 A – C, E – G, 30 A). Maxilliped 3 with well-developed flagellum on exopod (Fig. 29 B). Chelipeds relatively stouter in adult males (Figs. 27 A, E, 30 A). Ambulatory legs relatively stout, shorter, glabrous (Fig. 27 A, E). Male s 2 / s 3 visible as groove; male s 3 / s 4 only visible as 2 short lateral depressions (Fig. 27 D, H). Male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (Fig. 27 D, H). Male pleon relatively narrow, with concave lateral margins; pleonal somite 6 trapezoidal, relatively broad, proximal width ca. 1.3 – 1.9 times medial length (Figs. 27 D, H, 29 D). G 1 relatively slender; ultimate article subconical, inverted funnel-shaped, relatively slender, relatively short, ca. 0.3 times length of penultimate article; penultimate article slender (Figs. 28 A, B, D, E, 29 E, G). G 2 longer than G 1, ca. 1.2 – 1.4 times G 1 length; ultimate article long, ca. 0.4 – 0.5 times length of penultimate article (Figs. 28 C, F, 29 F, H). Vulvae relatively widely located from each other (VD / SW = ca. 0.2) (Fig. 29 J).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	etymology	Etymology. The genus name is derived from the Nilgiri Hills of the central Western Ghats of India, which is the type locality of the type species. The gender of this genus is feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	discussion	Remarks. Nilgiriana gen. nov. currently includes two species, Ni. nilgiriensis (Roux, 1931) comb. nov., and a new species, Ni. paloti sp. nov., described in the present study. Nilgiriana gen. nov. can be separated from other freshwater crab genera of southern India by the relatively low carapace (CH / CW = ca. 0.4) (Figs. 27 C, G, 30 A); the posterolaterally weakly developed postorbital cristae (Fig. 27 A, B, E, F); the broadly triangular external orbital angle, with the long outer margin, ca. 4 – 5 times the inner margin length (Fig. 27 A, B, E, F); the low epibranchial tooth (Fig. 27 A, B, E, F); the well-developed flagellum on the exopod of maxilliped 3 (Fig. 29 B); the relatively stouter pereiopods, with the ambulatory legs being shorter and glabrous (Figs. 27 A, E, 30 A); the male s 2 / s 3 discernible as groove (Fig. 27 D, H); the relatively slender G 1, with the subconical, inverted funnel-shaped and relatively short ultimate article (ca. 0.3 times the length of the penultimate article), and the relatively slenderer penultimate article (Figs. 28 A, B, D, E, 29 E, G); the distinctly longer G 2, ca. 1.2 – 1.4 times the G 1 length, with the long ultimate article, ca. 0.4 – 0.5 times length of penultimate article (Figs. 28, 29 E – H); the relatively widely located vulvae (VD / SW = ca. 0.2) (Fig. 29 J).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB7325DA8DBFA41FB787CB2.taxon	description	Geographical distribution. Nilgiriana gen. nov. is distributed only in the central Western Ghats of Karnataka (Kodagu district), Kerala (Kannur and Wayanad districts), and Tamil Nadu (Nilgiris district) in southern India (Roux 1931; Bott 1970 a, 1970 b; Bahir & Yeo 2007; Pati et al. 2019 c; present study) (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB23252A8DBFA9DFE8E7F0C.taxon	description	(Figs. 27 A – D, 28 A – C)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB23252A8DBFA9DFE8E7F0C.taxon	materials_examined	Type material. Lectotype: male (CW 24.7 mm, CL 18.5 mm) (MHNG, uncatalogued), India, Tamil Nadu State, Nilgiris District, Nilgiris, Avalanche, 11.315 ° N, 76.599 ° E, “ elev. 2100 m a. s. l. ”, coll. J. Carl, 18 January 1927.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB23252A8DBFA9DFE8E7F0C.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 24.7 mm). Carapace relatively broad (CW / CL = ca. 1.3 – 1.4), relatively low (CH / CW = ca. 0.4) (Fig. 27 A – C); epistome posterior margin with gently sinuous lateral lobes (Fig. 27 C); male s 2 / s 3 incomplete, not reaching edge of sternum (Fig. 27 D); male sternopleonal cavity relatively shorter, reaching to imaginary line joining medial part of cheliped coxae (Fig. 27 D); male pleon relatively broader, with relatively broad pleonal somite 6, proximal width ca. 1.9 times medial length (Fig. 27 D); male telson broader than long, medial length ca. 0.9 times proximal width, with concave lateral margins (Fig. 27 D); G 1 ultimate article subconical, inverted funnel-shaped, distally abruptly narrow, almost straight, short, ca. 0.3 times length of penultimate article (Fig. 28 A, B); G 1 penultimate article with gently sinuous outer margin (Fig. 28 A, B); G 2 distinctly longer than G 1, ca. 1.4 times G 1 length, ultimate article relatively longer, ca. 0.5 times length of penultimate article (Fig. 28 C).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB23252A8DBFA9DFE8E7F0C.taxon	discussion	Remarks. Nilgiriana nilgiriensis comb. nov. was originally described by Roux (1931) as Paratelphusa (Liotelphusa) nilgiriensis. Bott (1970 a, 1970 b) subsequently transferred the species to Gubernatoriana probably due to its weakly developed postorbital cristae. The lectotype designated for the species by Bott (1970 a, 1970 b) was also illustrated in Bahir & Yeo (2007). Bahir & Yeo (2007), however, assigned the species to Vanni, with arguments that the species differs from Gubernatoriana mainly by the well-developed flagellum on the exopod of the maxilliped 3 and the relatively long G 2 ultimate article. The species reported as Vanni nilgiriensis from Karnataka and Kerala by Pati et al. (2019 c) was actually Nilgiriana paloti sp. nov.; the differences between Nilgiriana nilgiriensis comb. nov. and the new species are discussed in detail (see remarks for the latter new species). Ecological notes. The ecology of Ni. nilgiriensis comb. nov. is so far not known, except for the fact that the species was reported to dwell at the higher elevations (2000 – 2200 m a. s. l.) of the central Western Ghats and found syntopic with Pu. pusilla comb. nov. at Avalanche of the Nilgiris Hills (see Roux 1931).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFB23252A8DBFA9DFE8E7F0C.taxon	description	Geographical distribution. Nilgiriana nilgiriensis comb. nov. is currently known only from the central Western Ghats in the Nilgiris district of Tamil Nadu, southern India (Roux 1931; Bott 1970 a, 1970 b; Bahir & Yeo 2007) (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	description	(Figs. 27 E – H, 28 D – F, 29, 30 A) Not Vanni nilgiriensis – Pati et al. 2019 c: e 2019006, fig. 2.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	materials_examined	Type material examined. Holotype: male (CW 20.8 mm, CL 15.4 mm, CH 8.5 mm, FW 6.4 mm) (ZSI-WRC C. 2477), India, Karnataka State, Kodagu District, Tadiandamolbetta, 12.230 ° N, 75.632 ° E, elev. 1196 m a. s. l., coll. B. Tripathy et al., 18 November 2023. – Paratypes: 4 males (CW 13.4 – 18.3 mm, CL 9.8 – 12.6 mm, CH 5.8 – 8.4 mm, FW 4.2 – 5.5 mm), 9 females (CW 14.6 – 19.1 mm, CL 10.6 – 13.3 mm, CH 6.4 – 8.1 mm, FW 4.6 – 6.0 mm) (ZSI-WRC C. 1826), India, Kerala State, Wayanad District, Pilakavu, 11.867 ° N, 75.985 ° E, elev. 859 m a. s. l., coll. P. S. Sujila, 9 October 2018. Other material examined. India – Karnataka State: 3 males (CW 14.0 – 15.2 mm, CL 10.5 – 11.5 mm, CH 5.7 – 5.9 mm, FW 4.5 – 4.8 mm), 3 females (CW 9.3 – 17.7 mm, CL 7.2 – 13.3 mm, CH 3.7 – 7.2 mm, FW 3.2 – 5.6 mm) (ZSI-WRC C. 2478), same collection data as for holotype; male (CW 24.4 mm, CL 17.2 mm, CH 9.3 mm, FW 8.0 mm) (ZSI-WGRC IR / INV / 9197), Kodagu District, Thalacauveri Wildlife Sanctuary, Ezhilaturn, 12.38359 ° N, 75.49418 ° E, elev. 1185 m a. s. l., coll. P. M. Sureshan, 6 November 2013; female (CW 8.1 mm, CL 6.3 mm, CH 3.2 mm, FW 2.7 mm) (ZSI-WRC C. 2480), Kodagu District, Talakaveri, 12.385 ° N, 75.496 ° E, elev. 1238 m a. s. l., coll. B. Tripathy et al., 17 November 2023. – Kerala State: male (CW 15.2 mm, CL 11.3 mm, CH 6.5 mm, FW 4.9 mm), 6 females (CW 8.0 – 14.6 mm, CL 6.1 – 11.1 mm, CH 3.3 – 6.4 mm, FW 3.0 – 4.8 mm) (ZSI-WRC C. 2479), Kannur District, Aralam Wildlife Sanctuary, 11.942 ° N, 75.864 ° E, elev. 438 m a. s. l., coll. B. Tripathy et al., 20 November 2023; 5 males (CW 12.3 – 18.6 mm, CL 8.2 – 13.4 mm, CH 4.9 – 8.0 mm, FW 4.0 – 5.9 mm), 4 females (CW 14.0 – 16.2 mm, CL 10.3 – 11.7 mm, CH 5.6 – 6.6 mm, FW 4.5 – 5.0 mm) (ZSI-WRC C. 2481), Wayanad District, Periya Range, Chandanathoodu, 11.846 ° N, 75.808 ° E, elev. 834 m a. s. l., coll. K. G. Emiliyamma, 4 April 2014; male (CW 15.6 mm, CL 11.4 mm, CH 6.6 mm, FW 4.9 mm), 3 females (CW 14.3 – 16.8 mm, CL 10.4 – 12.1 mm, CH 5.9 – 7.1 mm, FW 4.7 – 5.3 mm) (ZSI-WRC C. 1825), Wayanad District, Kambamala, 11.869 ° N, 75.942 ° E, elev. 816 m a. s. l., coll. P. S. Sujila, 26 October 2018.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 24.4 mm). Carapace relatively broad (CW / CL = ca. 1.3 – 1.5), relatively low (CH / CW = ca. 0.4) (Fig. 27 E – G); epistome posterior margin with strongly sinuous lateral lobes (Fig. 27 G); male s 2 / s 3 complete, reaching edge of sternum (Fig. 27 H); male sternopleonal cavity relatively longer, reaching to imaginary line joining anterior part of cheliped coxae (Fig. 27 H); male pleon relatively narrower, with relatively narrow pleonal somite 6, proximal width ca. 1.3 – 1.4 times medial length (Figs. 27 H, 29 D); male telson longer than broad, medial length ca. 1.1 – 1.2 times proximal width, with almost straight lateral margins (Figs. 27 H, 29 D); G 1 ultimate article subconical, inverted funnel-shaped, distally abruptly narrow, almost straight to gently curved outwards at ca. 10 ° from longitudinal axis of G 1, short, ca. 0.3 times length of penultimate article (Figs. 28 D, E, 29 E, G); G 1 penultimate article with strongly sinuous outer margin (Figs. 28 D, E, 29 E, G); G 2 longer than G 1, ca. 1.2 – 1.3 times G 1 length, ultimate article relatively shorter, ca. 0.4 times length of penultimate article (Figs. 28 F, 29 F, H); vulvae subovate, relatively large, occupying ca. 0.6 times length of s 6, located adjacent to s 5 / s 6, touching s 5 / s 6 (Fig. 29 J).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	description	Description of male holotype. Medium sized crab (CW 20.8 mm). Carapace transversely subovate, broader than long (CW / CL = ca. 1.3), low (CH / CW = ca. 0.4); dorsal surface glabrous, generally smooth except for epigastric and postorbital cristae and lateral surfaces; anterolateral surface gently inflated in frontal view; anterolateral margins gently convex, cristate with low granules, shorter than posterolateral margins; posterolateral margins converging posteriorly, gently concave medially; front broad (FW / CW = ca. 0.3), deflexed anteriorly, trapezoidal, anterior margin cristate with low granules, gently concave medially in dorsal view; frontal medial triangle incomplete, with dorsal margin only, lateral margins indiscernible; epigastric cristae well-developed, slightly anterior to postorbital cristae; postorbital cristae distinct but weakly developed posterolaterally, not reaching lateral margins of carapace; external orbital angle broadly triangular, with long outer margin, ca. 4 times length of inner margin; epibranchial tooth low but discernible; postorbital region concave; branchial regions low; cervical grooves shallow, broad, discontinuous, not reaching level of postorbital cristae; mesogastric groove deep, narrow, long, bifurcated posteriorly; H-shaped groove distinct; subhepatic region rugose, glabrous; suborbital region smooth, glabrous; pterygostomial region generally smooth, glabrous; supraorbital margin cristate, with low granules; suborbital margin concave, cristate with low granules, continuous with supraorbital margin; epistome posterior margin with well-developed, triangular medial tooth and strongly sinuous lateral lobes (Figs. 27 E – G, 30 A). Eyes large; eyestalk short, stout; cornea moderately large, pigmented (Figs. 27 G, 30 A). Antennules long, folded in longitudinally broad fossae; antennae shorter than eyestalk (Fig. 27 G). Mandibular palp with 2 articles; terminal article bilobed, anterior lobe narrow, long, posterior lobe broad, short, ca. 0.5 times length of anterior lobe (Fig. 29 A). Maxillipeds 1, 2 each with long flagellum on exopod (Fig. 29 A). Maxilliped 3 cover most of buccal cavity, when closed; ischium subrectangular, longer than broad, longitudinal medial groove indiscernible; merus subrectangular, broader than long, anterolateral corner rounded; exopod slender, distally narrow, reaching half-length of ischium, with well-developed flagellum, ca. 0.7 times width of merus (Figs. 27 G, 29 B). Chelipeds stout, generally smooth, glabrous, unequal, left chela larger (Figs. 27 E, 30 A). Major chela with 5 low, blunt teeth on each finger, remaining teeth small, small gape when fingers closed; dactylus gently curved, stout, longer than upper margin of palm, smooth; fixed finger stout, forming almost straight margin with ventral margin of palm; palm smooth, inflated, longer than high; carpus smooth, gently inflated, with prominent, broad, acute inner distal tooth and low, narrow, blunt basal tooth; merus smooth except for rugose or granular margins, lacking subterminal spine (Figs. 27 E, 30 A). Ambulatory legs generally smooth and glabrous, stout, short, P 3 longest; merus long, lacking subdistal spine; propodus and dactylus with distinct, sharp chitinous spines on margins; dactylus almost straight, subequal in length to propodus (Fig. 27 E). Thoracic sternites smooth, glabrous; s 1 and s 2 completely fused; s 2 / s 3 visible as narrow groove, reaching edge of sternum; s 3 / s 4 only visible as 2 short lateral depressions; s 4 / s 5, s 5 / s 6, s 6 / s 7 shallow, narrow, medially interrupted; s 7 / s 8 shallow, narrow, medially interrupted by longitudinal groove of s 7, lacking transverse ridge; s 8 completely covered by pleon, narrowed medially, longitudinal medial groove indiscernible (Figs. 27 H, 29 C). Pleonal locking mechanism with prominent tubercle on submedial part of s 5 (Fig. 29 C). Sternopleonal cavity deep, long, reaching to imaginary line joining anterior part of cheliped coxae (Figs. 27 H). Pleon narrow, triangular, with concave lateral margins; pleonal somites 1, 2 subrectangular, narrower than pleonal somite 3; pleonal somite 3 subrectangular, broadest, with convex lateral margins; pleonal somites 4, 5 trapezoidal, with straight lateral margins; pleonal somite 6 trapezoidal, broader than long (proximal width ca. 1.3 times medial length), distinctly longer than preceding pleonal somites, subequal in length to telson, with gently concave lateral margins (Figs. 27 H, 29 D). Telson bell-shaped, longer than broad (medial length ca. 1.1 times proximal width), with almost straight lateral margins, apex broad, rounded (Figs. 27 H, 29 D). G 1 slender, short, tip reaching beyond s 6 / s 7 up to half-length of s 6 in situ; ultimate article subconical, inverted funnel-shaped, slender, short, ca. 0.3 times length of penultimate article, almost straight, distal half abruptly narrow, tip acute; penultimate article sinuous, slender, broad at base, relatively narrow distally, inner margin sinuous, outer margin strongly sinuous; groove for G 2 median (Figs. 28 D, E, 29 E). G 2 longer than G 1, ca. 1.2 times G 1 length; ultimate article long, ca. 0.4 times length of penultimate article, with acute tip; penultimate article stouter at proximal third (Figs. 28 F, 29 F). Colour in life. Crabs are typically light to dark purplish-brown, with their dactylus of the major chelipeds generally conspicuously dark purplish-brown (Fig. 30 A).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	etymology	Etymology. The species name honours Dr. Muhamed Jafer Palot, a zoologist by profession and a naturalist by hobby. His contributions to the taxonomy and conservation of various faunal groups of the Western Ghats are noteworthy. He also helped in collecting this new species. The species name is treated here as a noun in the genitive singular.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	discussion	Remarks. The male paratypes and other males of N. paloti sp. nov. are similar to the holotype in the diagnostic characters for the species, especially in the strongly sinuous outer margin of the G 1 penultimate article (Fig. 29 G). Their carapace broadness only varies (CW / CL = ca. 1.3 – 1.5), so that those of the females (CW / CL = ca. 1.3 – 1.4). The female paratypes of the species also resemble the holotype in most of the non-sexual character states, especially the characteristic strongly sinuous lateral lobes of the epistome posterior margin. The adult females of N. paloti sp. nov. possess a pleon, which together with telson, forms an ovate outline covering the thoracic sternum except for s 1 – s 3 and lateral edges, when closed (Fig. 29 I). The pleonal somite 1 in adult females is the shortest; pleonal somites 2 – 5 are progressively longer; and pleonal somite 6 is the longest, conspicuously broader than long, subequal in length to the telson, with the convex lateral margins (Fig. 29 I). The adult female telson is broadly subtriangular to triangular, conspicuously broader than long, with straight to strongly convex lateral margins and broad apex (Fig. 29 I). The vulvae in adult females are widely located from each other (VD / SW = ca. 0.2) on the s 6; each vulva opens ventrally and is subovate, large, ca. 0.6 times the length of the s 6, located adjacent to the s 5 / s 6, touching the s 5 / s 6, the posterior margin with a raised rim, and covered by a soft membranous operculum (Fig. 29 J).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	description	Geographical distribution. Nilgiriana paloti sp. nov. is known only from the Bramhagiri Hills of the central Western Ghats in Karnataka (Kodagu district) and Kerala (Kannur and Wayanad districts), southern India (Pati et al. 2019 c; present study) (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	description	Genus Idukkiana gen. nov. (Figs. 31, 32)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	type_taxon	Type species. Vanni giri Bahir & Yeo, 2007, by present designation; gender of genus feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	diagnosis	Diagnosis. Medium sized crabs (maximum CW 18.8 mm). Carapace relatively broad (CW / CL = ca. 1.3), relatively low (CH / CW = ca. 0.4), with moderately convex lateral margins; frontal medial triangle incomplete, lateral margins indiscernible; postorbital cristae well-developed, reaching lateral margins of carapace; external orbital angle broadly triangular, with long outer margin, ca. 3.5 times length of inner margin; epibranchial tooth low, located at same level of postorbital cristae; epistome posterior margin with well-developed, triangular medial tooth and gently sinuous lateral lobes (Fig. 31 A, B). Maxilliped 3 with well-developed flagellum on exopod. Chelipeds relatively slender in adult male (see Bahir & Yeo 2007: fig. 44 B). Ambulatory legs relatively stout, shorter, glabrous (Fig. 31 A). Male s 2 / s 3 visible as very shallow groove, reaching edge of sternum; male s 3 / s 4 visible as shallow, complete groove, reaching edge of sternum (Fig. 31 C). Male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (Fig. 31 C). Male pleon relatively narrow, with concave lateral margins; pleonal somite 6 subquadrate, relatively narrow, proximal width ca. 1.1 times medial length, with straight lateral margins (Fig. 31 C). Male telson as long as broad, medial length ca. 1.0 times proximal width, with straight lateral margins (Fig. 31 C). G 1 relatively slender; ultimate article conical, relatively slender, distally gently curved outwards, relatively short, ca. 0.3 times length of penultimate article, tip acute and straight; penultimate article moderately stout, with almost straight outer margin (Fig. 32 A, B). G 2 longer than G 1, ca. 1.2 times G 1 length; ultimate article long, ca. 0.5 times length of penultimate article (Fig. 32 C).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	etymology	Etymology. The genus name is derived from Idukki, a district of Kerala that lies exclusively in the southern Western Ghats of India, and where the type species is originated. The gender of this genus is feminine.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFBC3255A8DBFF1CFA577FE2.taxon	discussion	Remarks. Idukkiana gen. nov. is established for the only species, Idukkiana giri (Bahir & Yeo, 2007) comb. nov., which was originally described in Vanni by Bahir & Yeo (2007). The new genus can be distinguished from Vanni s. str. in having a broadly triangular external orbital angle with a long outer margin, the presence of a discernible and complete groove of the male s 3 / s 4, and the fact that the male pleonal somite 6 has straight lateral margins (see remarks for Vanni). Idukkiana gen. nov. can easily be separated from the remaining gecarcinucid genera of southern India by its medium size (maximum CW 18.8 mm) in combination with the following morphological features: a carapace that is relatively low (CH / CW = ca. 0.4) (Fig. 31 B); well-developed postorbital cristae that reach the lateral margins of the carapace (Fig. 31 A); a broadly triangular external orbital angle, with a long outer margin, ca. 3.5 times the length of the inner margin (Fig. 31 A); a low epibranchial tooth (Fig. 31 A); a well-developed flagellum on the exopod of the maxilliped 3; relatively shorter ambulatory legs (Fig. 31 A); relatively shallow and complete male s 2 / s 3 and s 3 / s 4, which both reach the edge of the sternum (Fig. 31 C); a relatively shorter male sternopleonal cavity, which reaches the imaginary line joining the anterior part of the cheliped coxae (Fig. 31 C); a relatively narrow male pleon, with concave lateral margins (Fig. 31 C); a subquadrate, relatively narrow male pleonal somite 6, with the proximal width ca. 1.1 times the medial length, and straight lateral margins (Fig. 31 C); a male telson that is as long as broad, with the medial length ca. 1.0 times the proximal width, and straight lateral margins (Fig. 31 C); a G 1 ultimate article that is conical, relatively stouter, distally gently curved outwards and short, ca. 0.3 times the length of the penultimate article, with the relatively acute and straight tip (Fig. 32 A, B); a G 1 penultimate article that is relatively stout, with the outer margin almost straight (Fig. 32 A, B); and a distinctly longer G 2, ca. 1.2 times the G 1 length (Fig. 32). Among the freshwater crab genera of southern India, Idukkiana gen. nov. is morphologically closest to Naduganiana gen. nov. mainly due to the following shared characteristics: a low carapace (CH / CW = ca. 0.4) (Figs. 12 C, 31 B); well-developed postorbital cristae that extend to the carapace lateral margins (Figs. 12 A, B, E, 31 A); a broadly triangular external orbital angle with a long outer margin that is ca. 3 – 3.5 times the length of the inner margin (Figs. 12 A, B, E, 31 A); a low epibranchial tooth (Figs. 12 A, B, E, 31 A); relatively stouter and shorter ambulatory legs (Figs. 12 A, E, 31 A); a complete groove of the s 3 / s 4 (Figs. 12 D, 31 C); a subquadrate and relatively narrow male pleonal somite 6, with the proximal width ca. 1.1 – 1.2 times medial length (Figs. 12 D, G, 31 C); a relatively short G 1 ultimate article that is ca. 0.3 – 0.4 times the length of the penultimate article (Figs. 12 H, 13 A, 32 A); and a distinctly longer G 2 that is ca. 1.2 times the G 1 length (Figs. 12 H – J, 13, 32). These morphological similarities between the two genera notwithstanding, Idukkiana gen. nov. is nevertheless differentiated from Naduganiana gen. nov. by the relatively shallow male s 2 / s 3 and s 3 / s 4 (Fig. 31 C) (versus male s 2 / s 3 and s 3 / s 4 relatively deep; Fig. 12 D); the straight lateral margins of the male pleonal somite 6 and telson (Fig. 31 C) (versus male pleonal somite 6 and telson with the gently concave lateral margins; Fig. 12 D, G); the relatively stouter G 1 ultimate article, with the tip relatively acute and straight (Fig. 32 A, B) (versus G 1 ultimate article relatively slenderer, with the blunt and bent tip; Figs. 12 H, I, 13 A, B); and the relatively slenderer G 1 penultimate article, with an almost straight outer margin (Fig. 32 A, B) (versus G 1 penultimate article relatively stouter, with the sinuous outer margin; Figs. 12 H, I, 13 A, B). Although both genera are known from the Western Ghats in southern India, Idukkiana gen. nov. is restricted to the higher elevations (1570 m a. s. l.) of the southern Western Ghats (cf. Bahir & Yeo 2007) (Fig. 1 B), whereas Naduganiana gen. nov. is known only from the lower elevations (651 – 800 m a. s. l.) of the central Western Ghats (Bahir & Yeo 2007; present study) (Fig. 1 A). Geographical distribution. Idukkiana gen. nov. is known only from the higher elevations (1570 m a. s. l.) of the southern Western Ghats, specifically in the Idukki district of Kerala, southern India (Bahir & Yeo 2007) (Fig. 1 B).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFC4322DA8DBFF1CFA4E7FC7.taxon	description	(Figs. 31, 32)	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFC4322DA8DBFF1CFA4E7FC7.taxon	materials_examined	Type material. Holotype: male (CW 18.8 mm, CL 14.2 mm) (ZRC 2003.0271), India, Kerala State, Idukki District, “ between Munnar-Maraiyoor on Munnar-Pollachchi ” [between Munnar-Marayoor on Munnar-Pollachi road], 10.13172 ° N, 77.05578 ° E, elev. 1570 m a. s. l., collector and collection date unknown.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFC4322DA8DBFF1CFA4E7FC7.taxon	diagnosis	Diagnosis. As for new genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFC4322DA8DBFF1CFA4E7FC7.taxon	discussion	Remarks. According to Bahir & Yeo (2007), the G 2 ultimate article of Idukkiana giri comb. nov. is ca. 0.25 times the length of the penultimate article, which is certainly a typographical error. The G 2 ultimate article of the holotype is conspicuously long, ca. 0.5 times the length of the penultimate article (Fig. 32 C; see Bahir & Yeo 2007: fig. 43 E). The report of the species as Vanni giri by Pati et al. (2014) from the Chikkamagaluru and Kodagu districts of Karnataka is an error, which is evident from their figures (Pati et al. 2014: pl. 2 figs. 10 – 12, pl. 4 figs. 6 – 8). Their specimens actually belong to an undescribed species of Vanni (work in progress). The entire Idukki district of Kerala lies in the southern Western Ghats, which is currently known for 15 species in 12 genera (cf. Bahir & Yeo 2007; Pati & Sharma 2013; Pati et al. 2014, 2017; Rajesh et al. 2017; Raj et al. 2021, 2022; present study). Idukkiana giri comb. nov. can be easily separated from the species of those genera mainly by its distinctive characteristics, including its relatively small size (maximum CW 18.8 mm), a low carapace (CH / CW = ca. 0.4), a broadly triangular external orbital angle with a long outer margin (ca. 3.5 times the inner margin length), a low epibranchial tooth, a well-developed flagellum on the maxilliped 3 exopod, a relatively narrow male pleonal somite 6 (the proximal width ca. 1.1 times the medial length), a relatively shorter G 1 ultimate article (ca. 0.3 times the length of the penultimate article), and a distinctly longer G 2 with a length of ca. 1.2 times that of the G 1 (Figs. 31, 32). Ecological notes. Idukkiana giri comb. nov. was reported to inhabit moist soil and areas under stones, immediately adjacent to a streamlet, at an elevation of 1570 m a. s. l. (Bahir & Yeo 2007).	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFC4322DA8DBFF1CFA4E7FC7.taxon	description	Geographical distribution. As for new genus.	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
C436E549FFC4322DA8DBFF1CFA4E7FC7.taxon	description	– G 1 ultimate article and distal portion of penultimate article longitudinally twisted (see Pati et al. 2022 a: fig. 7 A – C) ..................................................................................... Spiralothelphusa Bott, 1968 [southern India; Maharashtra, Odisha, and West Bengal] 3. Orbit with lower outer corner channelled (see Pati & Sharma 2014: fig. 1 B) ....................................... ..................................................................... Gecarcinucus H. Milne Edwards, 1844 [Maharashtra; including northern Western Ghats] – Orbit with lower outer corner normal, not channelled (Fig. 2 B) ................................................. 4 4. G 2 distinctly shorter than G 1, ca. ≤ 0.7 × G 1 length (see Bahir & Yeo 2007: fig. 4 A, D; Pati & Thackeray 2018: figs. 4 D, F, 11 I, L, 17 I, L, 24 I, L; Pati et al. 2019 a: fig. 3 O, P; 2023 b: fig. 6 B, F; Pati & Yeo 2022: fig. 1 H, I, Q, R) .................... 5 – G 2 equal to or longer than G 1, ca. ≥ 1.0 × G 1 length (Figs. 3 A, C, 28 A, C) ...................................... 13 5. Male s 2 / s 3 indiscernible (see Pati & Thackeray 2018: figs. 4 C, 11 C, 17 C, 24 C); male sternopleonal cavity relatively long, reaching to or beyond imaginary line joining bases of maxilliped 3 (see Pati & Thackeray 2018: figs. 4 C, 11 C, 17 C, 24 C); G 2 ultimate article usually conspicuously short, ca. 0.1 × length of penultimate article (see Pati & Thackeray 2018: figs. 4 F, 11 L, 17 L, 24 L) ........................................................................................... 6 – Male s 2 / s 3 distinct (see Bahir & Yeo 2007: fig. 5 C; Pati et al. 2019 a: fig. 2 F; 2023 b: fig. 2 C; Pati & Yeo 2022: fig. 1 F, O); male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (see Bahir & Yeo 2007: fig. 5 C; Pati et al. 2019 a: fig. 2 F; 2023 b: fig. 2 C; Pati & Yeo 2022: fig. 1 F, O); G 2 ultimate article usually relatively long, ca. 0.2 – 0.3 × length of penultimate article (see Bahir & Yeo 2007: fig. 4 D; Pati et al. 2019 a: fig. 3 P; 2023 b: fig. 6 F; Pati & Yeo 2022: fig. 1 I) ........................................................................................ 9 6. Male telson elongated (see Pati & Thackeray 2018: figs. 4 C, 17 C, G) ............................................ 7 – Male telson relatively short (see Pati & Thackeray 2018: figs. 11 C, G, 24 C, G) .................................... 8 7. Front with relatively narrow anterior margin (FW / CW = ca. 0.4) (see Pati & Thackeray 2018: fig. 4 B); maxilliped 3 exopod relatively long, reaching beyond anterolateral corner of ischium (see Pati & Thackeray 2018: fig. 6 H); G 1 relatively stouter (see Pati & Thackeray 2018: fig. 4 D) ................................................. Ghatiana Pati & Sharma, 2014 [Goa, Karnataka, and Maharashtra; northern and central Western Ghats only] – Front with relatively broad anterior margin (FW / CW = ca. 0.5) (see Pati & Thackeray 2018: fig. 17 B); maxilliped 3 exopod relatively short, not reaching anterolateral corner of ischium (see Pati & Thackeray 2018: fig. 17 H); G 1 conspicuously slender (see Pati & Thackeray 2018: fig. 17 I) ................................................. Inglethelphusa Bott, 1970 [Maharashtra (Satara district); northern Western Ghats only] 8. Branchial regions relatively low (see Pati & Thackeray 2018: fig. 11 A); ambulatory legs with sparsely setose dactylus and propodus (see Pati & Thackeray 2018: fig. 11 A, E); male sternopleonal cavity relatively short, not reaching beyond imaginary line joining bases of maxilliped 3 (see Pati & Thackeray 2018: fig. 11 C) ..................... Gubernatoriana Bott, 1970 [Maharashtra; northern Western Ghats only] – Branchial regions relatively inflated (see Pati & Thackeray 2018: fig. 24 A); ambulatory legs with abundantly setose dactylus and / or propodus (see Pati & Thackeray 2018: fig. 24 A, E); male sternopleonal cavity relatively long, reaching beyond imaginary line joining bases of maxilliped 3 (see Pati & Thackeray 2018: fig. 24 C) ............. Sahyadriana Pati & Thackeray, 2018 [Maharashtra; northern Western Ghats only] 9. Carapace ovate, relatively narrow (CW / CL = ca. 1.2 – 1.4), relatively deep (CH / CW = ca. 0.5 – 0.7) (see Bahir & Yeo 2007: fig. 5 A, B; Pati et al. 2019 a: fig. 2 D, E; 2023 b: fig. 2 A, B); epistome posterior margin with strongly sinuous lateral lobes (see Bahir & Yeo 2007: fig. 5 B; Pati et al. 2019 a: fig. 2 E; 2023 b: fig. 2 B); male sternopleonal cavity relatively short, reaching to imaginary line joining medial part of cheliped coxae (see Bahir & Yeo 2007: fig. 5 C; Pati et al. 2019 a: fig. 2 F; 2023 b: fig. 2 C) ..... 10 – Carapace subovate, relatively broad (CW / CL = ca. 1.4 – 1.5), relatively low (CH / CW = ca. 0.4 – 0.5) (see Pati & Yeo 2022: fig. 1 A, B, J, K); epistome posterior margin with concave lateral lobes (see Pati & Yeo 2022: fig. 1 B, K); male sternopleonal cavity relatively long, reaching to imaginary line joining anterior part of cheliped coxae (see Pati & Yeo 2022: fig. 1 F, O) ...... 12 10. Male telson narrow, elongated, medial length ca. 1.3 – 1.4 × proximal width (see Pati et al. 2023 b: fig. 6 A); G 1 ultimate article relatively stouter (see Pati et al. 2023 b: fig. 6 B); G 1 penultimate article with characteristically convex distal inner margin (see Pati et al. 2023 b: fig. 6 B) ................................................ Aradhya Pati, Bajantri & Hegde, 2023 [Karnataka (Uttara Kannada district); central Western Ghats only] – Male telson relatively broader, shorter, medial length ca. 0.9 – 1.1 × proximal width (see Bahir & Yeo 2007: fig. 5 C; Pati et al. 2019 a: fig. 2 F); G 1 ultimate article relatively slender (see Bahir & Yeo 2007: fig. 4 A; Pati et al. 2019 a: fig. 3 O); G 1 penultimate article with almost straight distal inner margin (see Bahir & Yeo 2007: fig. 4 A; Pati et al. 2019 a: fig. 3 O) .............. 11 11. Carapace dorsal surface generally smooth, lacking distinct serrations on anterolateral margins (see Pati et al. 2019 a: fig. 2 A, D); cervical grooves relatively shallow (see Pati et al. 2019 a: fig. 2 A, D); maxilliped 3 lacking flagellum or with relatively short flagellum, reaching about half width of merus (see Pati et al. 2019 a: fig. 3 B, N); male pleonal somite 6 relatively broad, proximal width ca. 1.7 – 1.8 × medial length (see Pati et al. 2019 a: fig. 2 C, F); G 1 relatively stout, with large flexible zone (see Pati et al. 2019 a: fig. 3 E, O) .............................................. Arcithelphusa Pati & Sudha Devi, 2015 [Kerala (Wayanad district); central Western Ghats only] – Carapace dorsal surface relatively rugose, with distinct serrations on anterolateral margins (see Bahir & Yeo 2007: fig. 5 A; Pati et al. 2017: fig. 11 a); cervical grooves relatively deep (see Bahir & Yeo 2007: fig. 5 A; Pati et al. 2017: fig. 11 a); maxilliped 3 with relatively long flagellum, reaching beyond half width of merus (Pati et al. 2017: fig. 11 i); male pleonal somite 6 relatively narrow, proximal width ca. 1.3 – 1.6 × medial length (see Bahir & Yeo 2007: fig. 5 C; Pati et al. 2017: fig. 11 h); G 1 relatively slender, with small flexible zone (see Bahir & Yeo 2007: fig. 4 A; Pati et al. 2017: fig. 12 a) ....................................................................................................... Cylindrotelphusa Alcock, 1909 [Kerala and Tamil Nadu (Nilgiris district); including central and southern Western Ghats] 12. Epibranchial tooth low, weakly developed, located anterior to level of postorbital cristae (see Pati & Yeo 2022: fig. 1 J); cervical grooves relatively short, not reaching to level of postorbital cristae (see Pati & Yeo 2022: fig. 1 J); subhepatic region smooth (see Pati & Yeo 2022: fig. 1 K); major cheliped with relatively stout palm (see Pati & Yeo 2022: fig. 1 N); male pleon relatively broad, with trapezoidal and relatively broader pleonal somite 6, proximal width ca. 1.3 – 1.7 × medial length (see Pati & Yeo 2022: fig. 1 P); G 1 relatively long, tip reaching beyond s 5 / s 6, ultimate article relatively long, ca. 0.7 – 0.8 × length of penultimate article (see Pati & Yeo 2022: fig. 1 O, Q) ................................................ Barusa Pati & Yeo, 2022 [peninsular India, including southern India (Andhra Pradesh, Karnataka, and Telangana), and northern and central Western Ghats] – Epibranchial tooth distinct, relatively strongly developed, located at same level of postorbital cristae (see Pati & Yeo 2022: fig. 1 A); cervical grooves relatively long, reaching to level of postorbital cristae (see Pati & Yeo 2022: fig. 1 A); subhepatic region relatively rugose (see Pati & Yeo 2022: fig. 1 B); major cheliped with relatively slender palm (see Pati & Yeo 2022: fig. 1 E); male pleon relatively narrow, with subquadrate and relatively narrower pleonal somite 6, proximal width ca. 1.2 × medial length (see Pati & Yeo 2022: fig. 1 G); G 1 relatively short, tip reaching to proximal half of s 6, ultimate article relatively short, ca. 0.6 × length of penultimate article (see Pati & Yeo 2022: fig. 1 F, H) ........................... Barytelphusa Alcock, 1909 [peninsular India, including southern India and Western Ghats] 13. Maxilliped 3 completely lacking flagellum on exopod (see Bahir & Yeo 2007: figs. 25 B, 27 A) ...................... 14 – Maxilliped 3 with distinct flagellum on exopod (Figs. 16 E, 29 B) .............................................. 16 14. Postorbital cristae strongly developed (see Pati et al. 2017: fig. 2 a); external orbital angle acutely triangular, with short outer margin, ca. 2 × length of inner margin (see Pati et al. 2017: fig. 2 a); G 2 slightly longer than G 1, with relatively short ultimate article, ca. 0.3 × length of penultimate article (see Pati et al. 2017: fig. 3 a, d) .......................................................................................... Karkata Pati, Rajesh, Raj, Sheeja, Kumar & Sureshan, 2017 [Kerala (Ernakulam and Idukki districts); southern Western Ghats only] – Postorbital cristae indiscernible or weakly developed (see Bahir & Yeo 2007: figs. 25 A, 26 A, 28 A); external orbital angle broadly triangular, with long outer margin, ca. 3 – 4 × length of inner margin (see Bahir & Yeo 2007: figs. 25 A, 26 A, 28 A); G 2 distinctly longer than G 1, with relatively long ultimate article, ca. 0.4. – 0.5 × length of penultimate article (see Bahir & Yeo 2007: figs. 25 F, H, 27 C, G) ............................................................................ 15 15. Ambulatory legs with densely setose carpus, propodus, and dactylus (see Bahir & Yeo 2007: fig. 25 E); male s 2 / s 3 and s 3 / s 4 indiscernible (see Bahir & Yeo 2007: fig. 25 C) ......................................... Pilarta Bahir & Yeo, 2007 [Kerala (Ernakulam and Thiruvananthapuram districts); southern Western Ghats only] – Ambulatory legs with sparsely setose carpus, propodus, and dactylus (see Bahir & Yeo 2007: fig. 28 A); male s 2 / s 3 and s 3 / s 4 distinct, deep (see Bahir & Yeo 2007: figs. 28 C, 29 A) .................................... Snaha Bahir & Yeo, 2007 [Kerala (Idukki district) and Tamil Nadu (Dindigul district); southern Western Ghats only] 16. Postorbital cristae indiscernible (see Raj et al. 2022: fig. 3 B) ....................... Pavizham Raj, Kumar & Ng, 2022 [Kerala (Pathanamthitta district); southern Western Ghats only] – Postorbital cristae discernible, weakly to strongly developed (Figs. 2 A, 22 B, 25 B, 27 B) ............................ 17 17. Epibranchial tooth prominent, located posterior to level of postorbital cristae (see Bahir & Yeo 2007: fig. 23 A) ........... ............................................................................. Lamella Bahir & Yeo, 2007 [Kerala; including southern Western Ghats] – Epibranchial tooth relatively low, located at same level of postorbital cristae (Figs. 2 A, 12 B, 14 A, 25 B, 27 F) ........... 18 18. Carapace with strongly convex lateral margins (see Kumar et al. 2017: fig. 5 B); ambulatory legs exceptionally long, longest merus ca. 6 – 7 × longer than broad (see Kumar et al. 2017: figs. 5 A, 7 H) ................... Kani Kumar, Raj & Ng, 2017 [Kerala (Thiruvananthapuram district); southern Western Ghats only] – Carapace with gently to moderately convex lateral margins (Figs. 2 A, 12 B, 14 A, 25 B, 27 F); ambulatory legs relatively short, longest merus ca. ≤ 4 × longer than broad (Figs. 2 A, 12 A, 14 A, 25 A, H, 27 E) .................................... 19 19. Carapace deep (CH / CW = ca. 0.6) (see Raj et al. 2021: fig. 3 B); female vulvae closely located to each other (VD / SW = ca. 0.1) (see Raj et al. 2021: fig. 5 C) .............................................. Rajathelphusa Raj, Kumar & Ng, 2021 [Kerala (Idukki district); southern Western Ghats only] – Carapace usually low (CH / CW = ca. 0.3 – 0.5) (Figs. 10 B, 16 B); female vulvae located some distance from each other (VD / SW = ca. ≥ 0.2) (Figs. 10 F, 16 J) ............................................................................ 20 20. External orbital angle acutely triangular to triangular, with short outer margin, ca. 2 – 2.5 × length of inner margin (Figs. 14 A, 16 A, 18 A, 20 A, 22 A; see Bahir & Yeo 2007: figs. 19 A, 46 A) ................................................. 21 – External orbital angle broadly triangular, with long outer margin, ca. 3 – 5 × length of inner margin (Figs. 2 A, 4 A, E, 7 A, 10 A, 12 A, 25 A, 27 A, E, 31 A) .............................................................................. 24 21. Male s 3 / s 4 distinct, deep (see Bahir & Yeo 2007: figs. 18 A, 45 A) .............................................. 22 – Male s 3 / s 4 indiscernible (Figs. 14 C, 16 C, 18 D, 20 D, 22 D) ................................................... 23 22. Male pleonal somite 6 relatively broad, proximal width ca. 1.2 – 1.6 × medial length (see Bahir & Yeo 2007: fig. 18 B); G 1 ultimate article relatively stouter, broadly conical (see Bahir & Yeo 2007: fig. 18 C); G 2 ultimate article relatively short, ca. 0.3 × length of penultimate article (see Bahir & Yeo 2007: fig. 18 G) .......................... Baratha Bahir & Yeo, 2007 [Kerala (Idukki district); southern Western Ghats only] – Male pleonal somite 6 relatively narrow, proximal width ca. 0.8 – 0.9 × medial length (see Bahir & Yeo 2007: fig. 45 B); G 1 ultimate article relatively slenderer, narrowly conical / subconical (see Bahir & Yeo 2007: fig. 45 C); G 2 ultimate article relatively long, ca. 0.4 – 0.5 × length of penultimate article (see Bahir & Yeo 2007: fig. 45 F) ................ Vela Bahir & Yeo, 2007 [Karnataka (Kodagu and Uttara Kannada districts), Kerala (Idukki, Kozhikode, Palakkad, and Wayanad districts), and Tamil Nadu (Nilgiris district); central and southern Western Ghats only] 23. Postorbital cristae well-developed, reaching lateral margins of carapace (Figs. 14 A, 16 A, 18 A, B, 20 A, B); epistome posterior margin with well-developed, triangular medial tooth (Figs. 14 B, 16 B, 18 C, 20 C); male s 2 / s 3 discernible (Figs. 14 C, 16 C, 18 D, 20 D); male sternopleonal cavity relatively short, reaching to imaginary line joining anterior part of cheliped coxae (Figs. 14 C, 16 C, 18 D, 20 D); G 2 ultimate article relatively long, ca. 0.4 × length of penultimate article (Figs. 15 C, 17 C, 19 C, 21 C) .................................................................................... Vanni Bahir & Yeo, 2007 [Karnataka (as north as Uttara Kannada district), Kerala, and Tamil Nadu (as south as Kanyakumari district); central and southern Western Ghats only] – Postorbital cristae weakly developed posterolaterally, not reaching lateral margins of carapace (Fig. 22 A, B); epistome posterior margin with low, broadly triangular medial tooth (Fig. 22 C); male s 2 / s 3 indiscernible (Fig. 22 D); male sternopleonal cavity relatively long, reaching to imaginary line joining bases of maxilliped 3 (Fig. 22 D); G 2 ultimate article relatively short, ca. 0.3 × length of penultimate article (Fig. 24 C) .................................................. Santanusus gen. nov. [Kerala (Kozhikode, Palakkad, and Thrissur districts) and Tamil Nadu (Coimbatore district); central and southern Western Ghats only] 24. Postorbital cristae weakly developed posterolaterally, not reaching lateral margins of carapace (Figs. 25 A, B, 27 A, B, E, F; see Bahir & Yeo 2007: figs. 37 A, 38 A) ...................................................................... 25 – Postorbital cristae well-developed, reaching lateral margins of carapace (Figs. 2 A, 4 A, E, 7 A, 10 A, 12 A, 31 A) ......... 26 25. Chelipeds relatively slender in adult males (Fig. 25 G; see Roux 1931: fig. 16); ambulatory legs relatively slender, longer, setose (Fig. 25 A, H; see Roux 1931: fig. 16); male s 2 / s 3 indiscernible (Fig. 25 D; see Bahir & Yeo 2007: figs. 37 B, 38 C); male pleon with strongly concave, rather angular lateral margins (Fig. 25 D, I; see Bahir & Yeo 2007: figs. 37 C, 38 C); G 1 relatively stout, with conical ultimate article and relatively stouter penultimate article (Fig. 26 A, B; see Bahir & Yeo 2007: fig. 37 D, E) ......................................................................................... Pusillosa gen. nov. Tamil Nadu (Nilgiris district); central Western Ghats only] – Chelipeds relatively stout in adult males (Fig. 27 A, E); ambulatory legs relatively stout, shorter, glabrous (Fig. 27 A, E); male s 2 / s 3 discernible (Fig. 27 D, H); male pleon with relatively less strongly concave lateral margins (Figs. 27 D, H, 29 D); G 1 relatively slender, with subconical, inverted funnel-shaped ultimate article and relatively slenderer penultimate article (Figs. 28 A, B, D, E, 29 E) .................................................................... Nilgiriana gen. nov. [Karnataka (Kodagu district), Kerala (Kannur and Wayanad districts), and Tamil Nadu (Nilgiris district); central Western Ghats only] 26. Male s 3 / s 4 only visible as 2 short lateral depressions (Fig. 4 D, H); G 1 penultimate article slender (Fig. 5 A, B, D, E) ......................................................................................... Ponmudiana gen. nov. [Kerala (Kollam and Thiruvananthapuram districts) and Tamil Nadu (Kanyakumari and Tirunelveli districts); southern Western Ghats only] – Male s 3 / s 4 visible as complete groove, reaching edge of sternum (Figs. 2 C, 7 C, 10 D, 12 D, 31 C); G 1 penultimate article relatively stouter (Figs. 3 A, B, 8 A, B, 11 A, B, 13 A, B, 32 A, B) ............................................... 27 27. Male pleon relatively broad, with almost straight lateral margins, pleonal somite 6 trapezoidal (Fig. 7 C); G 1 ultimate article relatively stout, long, ca. 0.5 – 0.6 × length of penultimate article (Fig. 8 A, B) ....................... Palaniana gen. nov. [Kerala (Idukki, Palakkad, Pathanamthitta, and Thrissur districts) and Tamil Nadu (Coimbatore, Dindigul, and Theni districts); southern Western Ghats only] – Male pleon relatively narrow, with concave to strongly concave lateral margins, pleonal somite 6 subquadrate (Figs. 2 C, 10 D, 12 D, 31 C); G 1 ultimate article relatively slender, short, ca. 0.25 – 0.4 × length of penultimate article (Figs. 3 A, B, 11 A, B, 13 A, B, 32 A, B) .......................................................................................... 28 28. Male sternopleonal cavity relatively shorter, reaching to imaginary line joining medial part of cheliped coxae (Fig. 10 D); male pleonal somite 6 relatively broad, proximal width ca. 1.5 × medial length (Fig. 10 D, E) ............ Anamudiana gen. nov. [Kerala (Idukki district); southern Western Ghats only] – Male sternopleonal cavity relatively longer, reaching to imaginary line joining anterior part of cheliped coxae (Figs. 2 C, 12 D, 31 C); male pleonal somite 6 relatively narrow, proximal width ca. 1.1 – 1.2 × medial length (Figs. 2 C, 12 D, 31 C) ........ 29 29. Large sized crabs (maximum CW 55.3 mm); male telson relatively narrower, medial length ca. 1.2 × proximal width (Fig. 2 C); G 1 ultimate article distally gently curved inwards (Fig. 3 A, B); G 2 as long as G 1, ca. 1.0 × G 1 length (Fig. 3) ........................................................................................... Travancoriana Bott, 1969 [Tamil Nadu state (Nilgiris district); central Western Ghats only] – Medium sized crabs (maximum CW 28.0 mm); male telson relatively broader, medial length ca. 1.0 × proximal width (Figs. 12 D, 31 C); G 1 ultimate article distally gently to distinctly curved outwards (Figs. 13 A, B, 32 A, B); G 2 longer than G 1, ca. 1.2 × G 1 length (Figs. 13, 32) ............................................................................. 30 30. Male s 2 / s 3, s 3 / s 4 relatively shallow (Fig. 31 C); male pleonal somite 6 and telson with straight lateral margins (Fig. 31 C); G 1 ultimate article relatively stouter, with relatively acute and straight tip (Fig. 32 A, B); G 1 penultimate article relatively slenderer, with almost straight outer margin (Fig. 32 A, B) .............................................. Idukkiana gen. nov. [Kerala (Idukki district); southern Western Ghats only] – Male s 2 / s 3, s 3 / s 4 relatively deep (Fig. 12 D); male pleonal somite 6 and telson with gently concave lateral margins (Fig. 12 D); G 1 ultimate article relatively slenderer, with blunt and bent tip (Fig. 13 A, B); G 1 penultimate article relatively stouter, with sinuous outer margin (Fig. 13 A, B) ..................................................... Naduganiana gen. nov. [Kerala (Malappuram district) and Tamil Nadu (Nilgiris district); central Western Ghats only] General discussion Southern India is now known to have 63 species of freshwater crabs, belonging to 27 genera of the family Gecarcinucidae; whereas the Western Ghats is home to 81 species of gecarcinucid crabs, spanning 30 genera (Alcock 1910; Roux 1931; Bott 1970 b; Bahir & Yeo 2005, 2007; Pati et al. 2017, 2019 a, 2019 c, 2022 a, 2022 b, 2023 a, 2023 b, 2023 c, 2024; Rajesh et al. 2017; Pati & Thackeray 2018, 2021; Pati & Vargila 2019; Pati & Pradhan 2020; Raj et al. 2021, 2022; Mandal et al. 2022 a, 2022 b; Pati & Yeo 2022; present study) (Table 1). The southern Indian state of Kerala currently possesses 39 species of freshwater crabs in 22 genera, followed by Tamil Nadu with 20 species in 14 genera, Karnataka with 13 species in nine genera, Telangana with six species in four genera, and Andhra Pradesh with five species in four genera (Table 1). Among three major regions of the Western Ghats, the southern Western Ghats is now known for 18 genera and 31 species of freshwater crabs, the central Western Ghats for 14 genera and 23 species, and the northern Western Ghats for seven genera and 35 species (Table 1). The present taxonomic revision of the gecarcinucid freshwater crab genera, Travancoriana and Vanni, recognizes eight new genera and two new species from the Western Ghats of southern India based on the morphological and molecular evidence. This fact highlights the presence of many undescribed taxa in the region, warranting further exploration (Pati & Pradhan 2020). Freshwater crabs play important ecological roles in tropical ecosystems (Yeo et al. 2008; Cumberlidge et al. 2009), and a better understanding of the diversity, distribution, and ecology of freshwater crabs is essential for conservation and management efforts. The identification keys furnished here for the freshwater crab genera or species is a crucial step, which will help carcinologists currently working in the region. These identification keys, however, need refining with the discoveries of additional taxa in future. In conclusion, the taxonomy of freshwater crabs in southern India, especially in the Western Ghats, is still in a state of flux, and continued research is necessary to discover more taxa, resolve their phylogenetic relationships, and understand their diversity, distribution, and ecology. ...... continued on the next page ...... continued on the next page ...... continued on the next page	en	Z, Sameer Kumar Pati (2025): Taxonomic revision of the freshwater crab genera Travancoriana Bott, 1969, and Vanni Bahir & Yeo, 2007 (Crustacea: Decapoda: Gecarcinucidae), with descriptions of eight new genera and two new species from the Western Ghats, southern India. Zootaxa 5634 (1): 1-77, DOI: 10.11646/zootaxa.5634.1.1, URL: https://doi.org/10.11646/zootaxa.5634.1.1
