Capitamon meitei, Pati & Peter & L., 2024

Pati, Sameer K., Mitra, Santanu & Ng, Peter K. L., 2024, Identity of the freshwater crab Indochinamon beieri (Pretzmann, 1966), with the description of a new genus and four new species from northeastern India (Decapoda, Brachyura, Potamidae), Zoosystema 46 (23), pp. 589-615 : 605-606

Capitamon meitei n. sp.

( Figs 12 ; 13 ; 14 )

urn:lsid:zoobank.org:act:109C2D01-A922-4EE1-ABCE-710D7E91F2F2

TYPE MATERIAL. — Holotype. India • ♂ (51.7 × 38.8 mm); Manipur state: Thoubal district: Yairipok ; 24°39’53”N, 94°3’50”E; alt. 784 m; 24.XI.2018; Thangpurba Devi leg.; ZSI-WRC C.2405 .

Paratypes. India • ♂ (39.9 × 30.4 mm), ♀ (36.0 × 27.4 mm); Manipur state: Kangpokpi district : Leimakhong; 24°56’31”N, 93°50’27”E; alt. 884 m; 27.V.2019; Thangpurba Devi leg.; ZSI-WRC C.2406.

DIAGNOSIS. — Carapace ovate, broader than long ( CW /CL = 1.3- 1.4), relatively low ( CH /CW = 0.4); epigastric cristae well-developed, rugose; postorbital cristae well-developed, relatively sharp, oblique in dorsal view; external orbital angle triangular, with short outer margin, c. 2 × inner margin; epibranchial tooth low, blunt, positioned above level of postorbital cristae; cervical grooves continuous, reaching to level of postorbital cristae; epistome posterior margin with well-developed, triangular median tooth, outer parts sloping downwards laterally ( Fig. 12A, B ). Third maxilliped exopod with short flagellum, shorter than width of merus ( Fig. 13B ). Chelipeds rugose, unequal in adult males, inner distal tooth on carpus relatively broad ( Figs 12A, C ; 13C ). Male s3/s4 indiscernible ( Figs 12C ; 13D ). Male pleonal somite 6 relatively broader (proximal width c. 2.1-2.2 × medial length), equal in length to pleonal somite 5, with convex lateral margins ( Figs 12C ; 13E ). Male telson relatively broader (proximal width c. 1.3-1.4 × medial length), with gently to strongly concave lateral margins ( Figs 12C ; 13E ). G1 ultimate article relatively less strongly bent at angle of about 75° from longitudinal axis, with sinuous outer margin, dorsal flap relatively high, narrowly triangular ( Figs 13F ; 14A , C-E). G2 c. 1.2 × length of G1; ultimate article long, c. 0.5 × length of penultimate article ( Figs 13G ; 14B, D ). Vulvae laterally completely covered by protruding sternal cover, invisible in ventral view ( Fig. 13I ).

ETYMOLOGY. — The species name, meitei , means Manipuri, the people/language of Manipur. The name is used as a Latin noun in apposition.

GEOGRAPHICAL DISTRIBUTION. — Capitamon meitei n. gen., n. sp. is known only from Manipur state of northeastern India ( Fig. 1 ).

REMARKS

Among the nominal species of the genus, C. meitei n. gen., n. sp. most resembles C. mizoramense n. gen., n. sp. mainly by the G1 ultimate article, which has a sinuous outer margin, and the relatively high and narrowly triangular dorsal flap ( Figs 13F ; 14A , C-E; 16F; 17A, C-E). Capitamon meitei n. gen., n. sp. is nevertheless differentiated from C. mizoramense n. gen., n. sp. by the relatively less strongly bent G1 ultimate article, which is bent at an angle of about 75° from longitudinal axis of the G1 ( Figs 13F ; 14D, E ) (vs G1 ultimate article more strongly bent at an angle of about 110° from longitudinal axis of the G1; Figs 16F ; 17D, E ). In addition, the vulvae are completely covered laterally by the protruding sternal cover and invisible in the ventral view in C. meitei n. gen., n. sp. ( Fig. 13I ), whereas the vulvae are partially covered laterally by the protruding sternal cover and visible in the ventral view in C. mizoramense n. gen., n. sp. ( Fig. 16I ).

Figures

FIG. 12. — Capitamon meitei n. gen., n. sp., holotype ♂ (51.7 × 38.8 mm) (ZSI-WRC C.2405): A, overall dorsal view; B, frontal view of cephalothorax; C, overall ventral view. Scale bars: A, C, 20 mm; B, 10 mm.

FIG. 13. — Capitamon meitei n. gen., n. sp., holotype ♂ (51.7 × 38.8 mm) (ZSI-WRC C.2405) (A-G), paratype ♀ (36.0 × 27.4 mm) (ZSI-WRC C.2406) (H, I): A, mouthparts; B, right third maxilliped; C, chela (outer view); D, s1-s8 showing right G1 in situ; E, pleon and telson; F, left G1 (dorsal view); G, left G2; H, pleonal somites 3-6 and telson; I, s1-s8 showing vulvae. Scale bars: A, B, D, E, H, I, 5 mm; C, 10 mm; F, G, 2 mm.

FIG. 14. — Capitamon meitei n. gen., n. sp., holotype ♂ (51.7 × 38.8 mm) (ZSI-WRC C.2405): A, left G1 ultimate article (dorsal view); B, left G2; C, left G1 ultimate article (ventral view); D, left G1 (dorsal view); E, left G1 (ventral view). Scale bar: A, C, 1 mm; B, D, E, 2 mm.

FIG. 1. — Map showing Myanmar, India, northeastern India, and distribution of Indochinamon beieri (Pretzmann, 1966) and the species of Capitamon n. gen.

FIG. 16. — Capitamon mizoramense n. gen., n. sp., holotype ♂ (46.3 × 35.7 mm) (ZSIK C.6122/2A) (A-G), paratype ♀ (51.3 × 37.6 mm) (ZSIK C.6122/2B) (H, I): A, mouthparts; B, right third maxilliped; C, chela (outer view); D, s1-s8 showing right G1 in situ; E, pleon and telson; F, left G1 (dorsal view); G, left G2; H, pleonal somites 3-6 and telson; I, s1-s8 showing vulvae. Scale bars: A, B, D, E, H, I, 5 mm; C, 10 mm; F, G, 2 mm.

FIG. 17. — Capitamon mizoramense n. gen., n. sp., holotype ♂ (46.3 × 35.7 mm) (ZSIK C.6122/2A): A, left G1 ultimate article (dorsal view); B, left G2; C, left G1 ultimate article (ventral view); D, left G1 (dorsal view); E, left G1 (ventral view). Scale bar: A, C, 1 mm; B, D, E, 2 mm.