Uperodon systoma ( Schneider, 1799 )

Garg, Sonali, Senevirathne, Gayani, Wijayathilaka, Nayana, Phuge, Samadhan, Deuti, Kaushik, Manamendra-Arachchi, Kelum, Meegaskumbura, Madhava & Biju, Sd, 2018, An integrative taxonomic review of the South Asian microhylid genus Uperodon, Zootaxa 4384 (1), pp. 1-88 : 17-19

Uperodon systoma ( Schneider, 1799)

Marbled Globular Frog

( Figs. 1 , 2A–B , 3A , 4A–F , 5A ; Tables 1–4)

Original name and description. Rana systoma Schneider, 1799 . Historia amphibiorum naturalis et literarariae. Fasciculus primus. Continens Ranas, Calamitas, Bufones, Salamandras et Hydros in genera et species descriptos notisque suis distinctos. Jena: Friederici Frommanni, 144–146. Syntype. ZMB 3551, original description mentions two specimens, one likely to be lost. Type locality. “India orientali”, India. Current status of specific name. Valid name, as Uperodon systoma ( Schneider, 1799) . Synonyms. Engystoma marmoratum Cuvier, 1829 ( Duméril & Bibron 1841; Peters 1864 “1863”) and Systoma leschenaultii Tschudi, 1838 ( Duméril & Bibron 1841).

Note on doubtful synonym. Pachybatrachus Petersii Keferstein, 1868 described from “Neu-Süd-Wales” Australia was considered as a synonym of Uperodon systoma ( Schneider 1799) by Boulenger (1882) and followed by Parker (1934). However, if this taxon was indeed described from Australia (although it might be erroneous according to Frost 2017) it cannot be homogenous with Uperodon systoma or any other member of the genus Uperodon , which is clearly restricted to South Asia. Although, we could not examine the type of Pachybatrachus petersii Keferstein, 1868 , its synonymy with Uperodon systoma is considered doubtful.

Comments. The original description of Rana systoma ( Schneider 1799) mentions two specimens (= syntypes) from “ India orientali” but the description is likely to have been based on a single specimen ( Bauer 1998). Currently a single specimen is available in the ZMB (Berlin) collection ( Peters 1864 “1863”; Bauer 1998). We examined the available syntype (an adult female) and found it to clearly match the original description of the species. However, since at least two specimens were originally catalogued for this taxon and the original description was brief, we herein provide a detailed description of the available type specimen, ZMB 3551 (an adult female), as a reference of this species for future taxonomic works.

Comparison. Uperodon systoma differs from all other known members of the genus, except U. globulosus and U. taprobanicus , by its larger snout-vent size, male SVL 51–56 mm, female SVL 47–64 mm (vs. smaller, male SVL 21–40 mm, female SVL 28–43 mm); finger and toe tips rounded, without discs (vs. finger tips enlarged in to discs, except in U. globulosus ); and presence of two dermal projections on the neopalatinal ridges on posterior side of each choana, widely separated from the vomerine odontophores (vs. prominent dermal projections on the neopalatinal ridges on posterior side of each choana, narrowly separated from the vomerine odontophores in U. globulosus ; indistinct or weakly to well-developed neopalatinal ridges on posterior side of each choana, fused with the vomerine odontophores in all other species) ( Fig. 5A ). Uperodon systoma differs from U. globulosus and U. taprobanicus in having divided prevomers, as in the rest of Uperodon species (vs. undivided prevomers in U. globulosus and U. taprobanicus ) ( Parker 1934); and by its dorsum being light or dark brown with prominent yellow markings (vs. light brown to greyish-brown without any prominent markings in U. globulosus ; light to dark grey with prominent red or reddish-orange blotches in U. taprobanicus ). Specifically it also differs from U. globulosus by its snout length nearly equal to eye diameter, male EL/SL ratio 95.3–104%, N = 4, female EL/SL ratio 98–106%, N = 1 (vs. snout nearly twice as long as diameter of eye, male EL/SL ratio 40.5–50.0%, N = 3, female EL/SL ratio 44.4–54.8%, N = 1) ( Table 4 ).

Genetic divergence. For 16S mitochondrial gene sequences, the sampled populations of Uperodon systoma showed an average intraspecific distance of 0.9% (range 0–2.2%, N = 6). The sample from Bannerghatta (Karnataka) showed considerable divergence of up to 2.2% from the typical populations in Tamil Nadu, excluding which, U. systoma showed an average intraspecific distance of 0.5% (range 0–0.8%, N = 5). Genetically, U. systoma is closely related to U. globulosus , from which it was found to differ by an average uncorrected genetic distance of 3.5% (range 3.2–4.0%, N = 18). For interspecific genetic distances with all other members of the genus, see Table 3.

Description of syntype, ZMB 3551 (measurements in mm) ( Figs. 3A , 4A–D ). Large-sized (SVL 49.7), globular and robust adult female; head small (HW 11.7, HL 7.9, IFE 6.6, IBE 12.4), less than one-sixth (15.9%) of body length, wider than long (HW/HL ratio 1.5); snout semi-circular to nearly rounded in dorsal and ventral view, rounded in lateral view, its length (SL 4.8) nearly equal to horizontal diameter of eye (EL 4.9); loreal region obtuse with rounded canthus rostralis; interorbital space (IUE 4.8) nearly twice as wide as upper eyelid width (UEW 2.6); nostril oval without lateral flap of skin, nearly equidistant to tip of the snout (NS 1.6) and the eye (EN 1.4); tympanum not visible externally, distinct supratympanic fold extending from posterior corner of upper eyelid near to insertion of forelimb at axilla; eye diameter (EL 4.9); vomerine odontophores present on the palate, prominent, without teeth; presence of two prominent dermal projections on the neopalatinal ridges on posterior side of each choana, widely separated from the vomerine odontophores; tongue moderately large, rounded, shallowly emarginated. Forelimbs moderately short and strong; forearm (FAL 13.2) shorter than hand length (HAL 23.8); finger length formula I<IV<II<III (FI 3.5, FII 5.1, FIII 6.7, FIV 3.6); tips of all fingers rounded, without discs; webbing absent between fingers; subarticular tubercles weakly-developed, oval, all present; two well-developed palmar tubercles (inner, oval, 1.3 mm long; outer, bilobed, 1.7 mm long). Hind limbs relatively short and strong, thigh length (TL 18.3) longer than shank (SHL 15.4) and shorter than foot (FOL 18.6); tips of all toes rounded, without discs; webbing present, small: I2 – 2II1 3/4 – 3 III3 – 4 – IV4 – 2 3/ 4V; well-developed dermal fringes present on all toes; subarticular tubercles weakly-developed, oval, all present; two shovel-shaped metatarsal tubercles (inner, 2.3 mm long; outer, 4.3 mm long).

Skin of dorsum, sides of head, and dorsal parts of forelimb, thigh, tibia and tarsus, shagreened ( Fig. 3A ); posterior parts of thigh, especially cloacal region, granular. Ventral surfaces shagreened and wrinkled ( Fig. 3A ).

Colouration. In preservation (ZMB 3551): Dorsum brown with prominent light grey elongate blotches, flanks lighter in colour than dorsum; forelimbs, dorsal surfaces of thigh, shank and foot, light creamish-brown with darker brown markings; chest, belly, and ventral surfaces of thigh, tibia and foot grey with creamish-brown ( Figs. 3A , 4A– D ). In life (SDBDU 2005.2732): Dorsum brown with prominent yellow blotches, dorsal surface of head yellowish brown, upper eyelids yellow; lateral surfaces of head and flank lighter in colour compared to dorsum; forelimbs, dorsal surfaces of thigh, shank and foot, light brown with yellow blotches; throat, chest, and belly, greyish-white without any marking, ventral surfaces of forelimb, thigh, tibia and foot, white ( Figs. 4E–F ).

Variations. Morphometric measurements for six specimens are given in Table 4 . SDBDU 2005.2806: subarticular tubercles on fingers weakly-developed, throat greyish-white with light brown marbling; SDBDU 2005.2787: Skin of dorsum and limbs coarsely glandular, posterior parts of thigh especially the cloacal region prominently glandular, and throat coarsely granular.

Secondary sexual characters. Male (SDBDU 2005.2787): vocal sac externally visible on the lower jaw; female (SDBDU 2005.2806): ova white, pigmented on pole (diameter 0.9–1.3 mm, N = 10).

Geographical distribution and habitat. Uperodon systoma is widely distributed in India and Sri Lanka, and also reported from adjoining regions in Nepal and Pakistan ( Fig. 2B ). In India, it has been reported from the states of Tamil Nadu, Kerala, Karnataka, Maharashtra, Gujarat, Andhra Pradesh, Telangana, Odisha, Madhya Pradesh, Chhattisgarh, Rajasthan, Uttar Pradesh, Himachal Pradesh, West Bengal, Assam and Mizoram. In Sri Lanka, the species is known from Central, Eastern, Northern, North Western, Sabaragamuwa, Southern and Uva Provinces. For detailed list of localities and references thereto see Supplementary Table S1. In the present study, this species was found in Tamil Nadu (Coimbatore and Kunnapattu), Karnataka (Bannerghatta) and Odisha in India, and Dambulla (Central Province) in Sri Lanka ( Table 1). Individuals were collected from soil surface close to temporary pools or dry burrows in agricultural fields. See ‘Natural history and breeding’ observations in the respective section, after the species accounts.

Figures

FIGURE 1. Maximum Likelihood phylogram based on 511 bp of mitochondrial 16S rRNA gene sequences from 73 individuals representing all known members of the genus Uperodon. Three samples representing taxon under synonymy are shown inquotationmarks.Outgroup not shown for graphical purposes.BayesianPosterior Probabilities and bootstrap values of>50 are shown above and below the branches, respectively. Values towards the species labels represent mean uncorrected genetic distances between the species with range values in parentheses.

FIGURE 2. A. Geographic distribution of the genus Uperodon in Bangladesh, Bhutan, India, Nepal, Pakistan and Sri Lanka; B. Distributionof Uperodon globulosus, U. systomaand U.taprobanicus; C. Distribution of four endemic Uperodon species of the Western Ghats (excluding the widely distributed Indian member U. variegatus, shown in Fig.12A); D. Distribution of four endemic Uperdodon species of Sri Lanka. Details of localities reported in the present study are provided in Table 1. Records from literature are listed in supplementary Table S1 and indicated here based onapproximate coordinates.

FIGURE 3. Preserved type specimens of Uperodon species in dorsal and ventral view. A. Uperodon systoma, Syntype, ZMB 3551 (female); B. Uperodon globulosus, Syntype, NHM 62.12.29.4 (ex. BMNH 1947.2.10.97) (female); C. Kaloula pulchra taprobanica, Holotype, NHM 1905.3.25.138 (ex. BMNH 1947.2.10.62) (female); D. Ramanella anamalaiensis, Neotype, ZSI/ WGRC/V/A/956 (male); E. Hylaedactylus montanus, Holotype, NHM 72.4.17.212 (ex. BMNH 1947.2.11.19) (female); F. Ramanella mormorata, Neotype, ZSI/WGRC/V/A/958, (female); G. Ramanella nagaoi, Holotype, WHT 2826 (male); H. Callula obscura, Holotype, NHM 58.11.28.42 (ex. BMNH 1947.2.11.20) (female); I. Ramanella palmata, Holotype, NHM 90.11.8.62 (ex.BMNH 1947.2.11.21); J. Callula triangularis, Lectotype, NHM 74.4.29.897 (ex.BMNH 1947.2.11.15) (male); K.Hylaedactylus carnaticus, Lectotype, ZSI 2761(female); L. Uperodonrohani sp. nov., Holotype, DZ1449 (male).(Images: SD Biju and Sonali Garg).

FIGURE 4. A–D. Uperodon systoma (Syntype, ZMB 3551) in preservation: A. lateral view of head; B. ventral view of hand; C. ventral view of foot; D. schematic illustration of foot webbing; E–F. Uperodon systoma (SDBDU 2005.2732, female) in life:E. dorsolateral view; F. anterior view; G–J.Uperodon globulosus (Syntype, NHM 62.12.29.4 ex. BMNH 1947.2.10.97) in preservation:G. lateral view of head; H. ventral view of hand; I. ventral view of foot; J. schematic illustration of foot webbing; K–L. Uperodon globulosus (SDBDU 2014.2672, male) in life: K. anterior view (not preserved); L. dorsolateral view; M–P. Uperodon taprobanicus (Holotype, NHM 1905.3.25.138 ex. BMNH 1947.2.10.62) in preservation:M. lateral view of head; N. ventral view of hand; O. ventral view of foot; P. schematic illustration of foot webbing. (Images: SD Biju).

FIGURE 5. Ventral surface of the palate in Uperodon species showing vomerine odontophores separated or fused with dermal projectionsand/or neopalatinalridgeson posterior sides ofthe choanae (indicated witharrows).A. Uperodon systoma, SDBDU 2005.2787 (female) and SDBDU 2005.2806 (male); B. Uperodon globulosus, SDBDU 2014.2673 (female) and SDBDU 2005.4762 (female); C. Uperodon taprobanicus, SDBDU 2007.6364 (female) and SDBDU 2005.4732A (male); D. Uperodon anamalaiensis, SDBDU 2013.2302 (female) and SDBDU 2002.3050 (male); E. Uperodon montanus, SDBDU 2002.24B (female) and SDBDU 2003.40115 (male); F. Uperodon mormorata, SDBDU 2011.507 (male) and SDBDU 2012.43 (male); G. Uperodon obscurus, DZ 1366 (male); H. Uperodon palmatus, DZ 1331 (male); I. Uperodon triangularis, SDBDU 2007.6400 (female) and ZSI/WGRC/V/A/959 (male); J. Uperodon variegatus, SDBDU 2005.4726 (female) and SDBDU 2005.4727 (male); K.Uperodon rohani sp. nov., DZ 1521 (male).(Images:SD Biju).