Rhinophis erangaviraji, Mendis Wickramasinghe, L. J., Vidanapathirana, Dulan Ranga, Wickramasinghe, Nethu & Ranwella, P. Nayanaka, 2009

Mendis Wickramasinghe, L. J., Vidanapathirana, Dulan Ranga, Wickramasinghe, Nethu & Ranwella, P. Nayanaka, 2009, A new species of Rhinophis Hemprich, 1820 (Reptilia: Serpentes: Uropeltidae) from Rakwana massif, Sri Lanka, Zootaxa 2044, pp. 1-22 : 6-15

publication ID	https://doi.org/ 10.5281/zenodo.186405
DOI	https://doi.org/10.5281/zenodo.4583748
persistent identifier	https://treatment.plazi.org/id/03EF5940-C923-FF98-AC8E-3D86FB50FEAF
treatment provided by	Plazi
scientific name	Rhinophis erangaviraji
status	sp. nov.

Treatment

Rhinophis erangaviraji sp. nov.

Figs. 3–12 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 View FIGURE 9 View FIGURE 10 View FIGURE 11 View FIGURE 12 .

Holotype: NMSL 20080601, adult male 214 mm SVL, Enselwatte Estate, Sinharaja Division (Army Camp Forest), Rakwana hills, Matara District, Southern Province (N 06º 23', E 080º 36'), 1042 m. Coll. Dulan Vidanapathirana, Nayanaka Ranwella and L. J. M. Wickramasinghe. 5 December, 2007.

Paratypes: NMSL 20080602, adult female 291 mm SVL; NMSL 20080603, adult male 204 mm SVL; NMSL 20080604, adult female 241 mm SV; NMSL 20080605, small male 103 mm SVL. Collection data as for holotype.

Diagnosis: The new species is distinguished morphologically from the congener it resembles most closely, R. blythii , by the following characters: 146–157 (vs 159–165) paravertebral scales; 142–154 (vs 155–162) ventral scales ( Table 2); dorsal and lateral surface of head black (vs dark brown with dorsal yellow ‘V’, Fig 5 View FIGURE 5 & 6 View FIGURE 6 ); ventrally black zigzag pattern on yellow background (vs each ventral scale anterior blackish brown and posterior light brown, with brownish tint throughout ventrally, Fig 7 View FIGURE 7 ); no ring-like pattern at the base of the tail (vs yellow ring at base of tail, Fig 8 View FIGURE 8 , 9 View FIGURE 9 ); caudal shield with one axis of symmetry, narrower anteriorly (vs shield oval, with two axes of symmetry, Fig 10 View FIGURE 10 ); anal region and under side of tail black (vs anal region whitish brown, underside of tail dark brown, Fig 11 View FIGURE 11 ).

Rhinophis erangaviraji sp. nov. differs from, R. dorsimaculatus , R. oxyrhynchus , R. porrectus and, R. punctatus by having a smooth rostral (vs strongly ridged above); 142–154 ventrals (vs 238, 211–227, 281, and 236–246 ventrals, respectively); total length 300 mm (vs 350 mm, 573 mm, 350 mm, and 390 mm, respectively); moderate sized tail shield (vs large shield). Differs from R. oxyrhynchus , R. porrectus , and R. punctatus by having a shorter rostral, about one third (vs about one half) length of the dorsal head shield scales. Differs from R. homolepis and R. tricoloratus by smooth rostral (vs slightly ridged above); fewer ventrals (vs 180–204 and 163–175, respectively); moderate sized tail shield (vs large shield). Differs from R. drummondhayi by fewer ventrals (vs 173–191); moderate sized shield (vs small shield). Differs from R. philippinus by having generally fewer ventrals (vs 153–182 ventrals); moderate sized tail shield (vs large shield); and yellow markings (vs no yellow).

The three Indian species of Rhinophis differ from the new species as follows: R. fergusonianus has more ventrals (180), R. sanguineus has more ventrals (182–218) and 15 costal scale rows at midbody, and R. travancoricus has fewer ventrals (132–146) and lacks yellow markings on the body (confined to tail). As far as is known, no species of uropeltid snake occur in both India and Sri Lanka ( Cadle et al., 1990; McDiarmid et al., 1999; Bossuyt et al., 2004).

Description of holotype: Robust snake; snout-vent length (SVL) 214 mm; body elongate (SVL/BW ratio 21.70); head narrow; snout pointed; nostril small, smaller than the eye, situated at the anterior of nasal scale; eye small, diameter about one third of ocular shield; neck not obvious; tail short (SVL/TL 22.43). Rostral unkeeled, slightly compressed, shorter than frontal and parietal (FL/RL 1.19, PL2/RL 1.26), longer than nasals, prefrontals, and ocular (RL/NL 1.46, RL/ PFL 1.80, RL/AOW 1.14), about one third length of head (HL/RL 3.18); nasals completely separated by rostral, larger than prefrontal, smaller than ocular, frontal and parietal (NL/PFL 1.23, AOW/NL 1.27, FL/NL 1.74, PL1/NL 1.53, PL2/NL 1.84), anterior, lower, posterior, and upper edges touching rostral, 1st and 2nd supralabial, and prefrontal respectively; prefrontals contact frontal, ocular, 2nd and 3rd supralabials; frontal long (FL/FW2 1.37), touching parietals and oculars; ocular as long as wide, longer than prefrontal (AOW/PFL 1.57), shorter than parietal lengths 1 and 2 (AOW/PL1 1.35, AOW/PL2 0.69); ocular contacts parietal, 3rd and 4th supralabials; parietal similar in length to frontal (FL/PL2 0.95), contacting 4th supralabial and interparietal; interparietal slightly longer than wide, similar in length to nasal (NL/IPL 0.95); four supralabials, in size order 1st<2nd<3rd<4th, 4th four times as long as 1st; mental triangular, no mental grove, width greater than length, smaller than infralabials, touching 1st infralabial and postmental; postmental single, 1st pair of infralabial separated by postmental; three infralabials, second largest, third smallest; costals smooth, costal row counts 19, 17, 17; 155 paravertebral scales; 151 ventrals, each approximately twice as wide as long; preanal wider than length, equal in size to ventrals (PRW/WVA20 0.98); anal divided/paired, larger than preanal (AW/PRW 1.88); nine subcaudals, all entire; caudal shield suboval, with one axis of symmetry, anterior narrower than posterior, conical and blunt tip, ten scales around shield. (Tables 1, 2).

Rhinophis erangaviraji Rhinophis blythii

Holotype Paratype Paratype Paratype

20080601 20080602 20080603 20080604 20081501 20081502 20081503 20081504 PARA 154 156 146 155 158 163 160 165 SASH 10 13 12 12 11 10 9 12 SUBC 9 6 8 5 5 5 4 6 VEN 149 152 140 151 153 162 157 156 Colour in life: Head black with yellow irregular spots. Lower margin of supralabials bright yellow. Eye black, rounded pupil not prominent. Dorsal body black, lower margins of costal scales with small irregular yellow spots. Lateral surface of body with canary yellow, scalloped stripe from gape to just behind anterior of tail shield. Scalloped nature prominent in first third of stripe, and close to vent, stripe less prominent on middle of body, ends in straight line on tail. Scalloping of lateral stripe extends onto ventral surface of body. Tail pitch except laterally. Shield black, with very small spines trapping small grains of sand and mud giving it a brownish tint.

Colour in alcohol: Colour pattern remains unchanged. Pupil changes to yellowish white. Black on dorsum changes to dark brown, bright yellow to off white.

Paratypes and variations: Subcaudals divided in all paratypes. However, about 75% of nearly 40 other (living and dead) specimens examined had entire subcaudals. A summary of the morphological and morphometric data of the paratypes is given in Table 1. Small R. erangaviraji have been found readily during October to January. The colour pattern of these younger animals is as in adults, with overall paler colours but a much darker head ( Fig 12 View FIGURE 12 ). Paratype NMSL20080604 has seven maxillary and seven mandibular teeth on each side.

Etymology: Named for the late Mr. Eranga Viraj Dayarathne, an Instructor of the Reptiles group of the Young Zoologists’ Association of Sri Lanka, Department of National Zoological Gardens. A man who showed love and kindness to nature, and quiet yet effective service to Sri Lankan reptiles and their conservation. Suggested vernacular names: Eranga Virajge thudulla, Eranga Virajvin nilakael pambu, Eranga Viraj’s shieldtail snake (or Eranga Viraj's Rhinophis ) in Sinhala, Tamil, and English respectively.

Comparison: Apart from the listed diagnostic characters, R. erangaviraji can be distinguished further from all other Sri Lankan congeners in details of its colour pattern. Rhinophis dorsimaculatus has a broad orange, middorsal vertebral stripe (vs black dorsal body colour); R. drummondhayi has a dappled brown and white or pale yellow venter (vs black with yellow), a whitish (vs black) anal region and a yellow-white ring at the base of the tail (vs absent); R. homolepis has a white/yellow collar behind the head (vs dorsal surface of neck black), white/yellow triangular (apex pointed upwards) markings along body (vs scalloped yellow stripe), yellow anal (vs black), and pale yellow ring at base of tail (vs absent); R. oxyrhynchus has a uniformly brown dorsal colour (vs black), pale brown to yellow or whitish venter (vs black with yellow), and yellow anal (vs black); R. philippinus has a purplish-black dorsum (vs black) and lateral and ventral surface of body (vs black with yellow markings); R. porrectus and R. punctatus have a whitish venter (vs black), and a narrow dark dorsal stripe (vs no stripe); R. tricoloratus has a yellow to yellow-brown venter (vs black with yellow markings), gray to brown dorsum (vs black), yellow to whitish yellow anal (vs black), and a yellowish ring at base of tail (vs absent).

Habitat, Ecology and Conservation: Rhinophis erangaviraji and R. blythii are allopatric, with the former known only from the Rakwana massif and the latter from the Central Hills, of Sri Lanka. Rhinophis erangaviraji can be found without difficulty in loose soil in shady areas, up to 1 m deep, under leaf litter in drainage ditches in tea estates, home gardens, and grasslands, but is also relatively commonly seen within the natural forest habitat of Rakwana. At night these snakes can be seen in the leaf litter. Probable conservation threats to this species are habitat loss, and deterioration caused by agriculture (especially tea), including the use of agrochemicals. Forest fires started by humans during the dry season are another threat, as indicated by many dead specimens being found after these fires. Road kills have also been observed.