de Silva’s Rough-Side Snake

description

Comparison. The new species was compared with all known congeners of the genus Aspidura and the species most closely resembles A. ravanai, and A. trachyprocta, due to the following combination of characters: one preocular, two postoculars, 1 + 2 temporals, supralabials 6, 4 th supralabial in contact with the eye, infralabials 6, coastals 15, single cloacal scale, and overlapping ventral and subcaudal counts, but can easily be distinguished by the following morphological characters: from A. ravanai: entire dorsum brown colour, much paler towards anterior and each scale having tiny dark spots in Aspidura desilvai sp. nov. (vs. entire dorsum jet black in Aspidura ravanai), ventrolaterally darker region which constitutes of irregular longitudinal dotted lines (vs. ventrolaterally an irregular longitudinal yellow stripe), laterally prominent spine like tubercles present on two scale rows nearest to the subcaudals, and its protrusion reducing towards upper scale rows (vs. entire coastal rows coarsely keeled, with 1 – 3 peaks on each scale) in males (Figures 4 & 10 A – C), entire coastal rows of the ischiadic, anal and tail base regions smooth (vs. feebly keeled) in females, snout to eye

A new species of Aspidura Wagler, 1830 (Squamata: Colubridae: Natricinae) from Knuckles, World Heritage Site, Sri Lanka

description

Description of holotype. Adult male; SVL 168 mm; TaL 25.1 mm; TL 193.1 mm; TaL / TL 0.13; body elongate and cylindrical; head short (SVL / HL 18.3), elliptical, indistinct from thick neck; snout long, narrowing anteriorly, pointed in dorsal aspect, snout to nostril distance about 2.8 (EW / SN) times as long as nostril width; nasal divided; small, triangular nostril, touching divided nasal and first supralabial, not touching rostral; eye larger than horizontal diameter of nostril, distance between snout to eye about 2.6 (SE / EW) times the eye width, round pupil; snout to eye distance 0.3 times head length (SE / HL); tail short (TaL / SVL 0.1), robust at its base, tapering progressively to a single point. Head scalation. Head scalation includes 1 internasal, 2 prefrontals, 2 supraoculars, 1 frontal, and 2 parietals (Figure 3 A). Rostral small, convex, wider than long and rounded in lateral, dorsal and ventral aspects. Nasal vertically divided by a groove above nostril (Figure 3 B). Internasal large, irregular hexagonal; widely in contact with prefrontals. Two large prefrontals, longer and wider than internasals, largest distance along the longitudinal axis of prefrontals shorter tha

A new species of Aspidura Wagler, 1830 (Squamata: Colubridae: Natricinae) from Knuckles, World Heritage Site, Sri Lanka

diagnosis

Diagnosis. SVL 94 – 216 mm; snout to eye distance 2.5 times the eye width (SE / EW); prefrontals touching eye; preocular small, does not touch supraocular; postoculars 2, lower one larger than the upper; temporal 1 + 2 / 1 + 2; supralabials 6 / 6, 4 th touching eye; infralabials 6 / 6, first pair in contact, progressively increasing in size from 1 st to 6 th; anterior chin shields 2, large, touching 1 – 4 infralabials; posterior chin shields 2, anterior half in contact while the posterior half separated by 1 st ventral; ventrals 124 – 139; subcaudals 16 – 29; dorsal scale rows 15 – 15 – 15; laterally spine like tubercles present on two scale rows nearest to the subcaudals of the ischiadic, anal and tail base regions in adult males, feeble in juvenile males, and absent in females; entire dorsum brown colour, much paler towards anterior; three irregular dotted lines on dorsum.

A new species of Aspidura Wagler, 1830 (Squamata: Colubridae: Natricinae) from Knuckles, World Heritage Site, Sri Lanka

etymology

Etymology. The species is named in honor of Pilippu Hewa Don Hemasiri de Silva (Dr. P. H. D. H. de Silva), a former Director (1965 - 1981) of the National Museums of Sri Lanka. In recognition of his tireless services to the country, while in service and through his many publications specially as the author of the book titled “ Snake Fauna of Sri Lanka, with special reference to skull, dentition and venom in snakes ”. The species epithet desilvai is a noun in the genitive case. Suggested common names. desilvage madilla, and de Silva’s Rough-Side Snake in native Sinhala language and English language respectively.

A new species of Aspidura Wagler, 1830 (Squamata: Colubridae: Natricinae) from Knuckles, World Heritage Site, Sri Lanka