Hypnale zara Gray 1849
Creators: name: Maduwage, Kalana
name: Silva, Anjana
name: Manamendra-Arachchi, Kelum
name: Pethiyagoda, Rohan
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Reptilia
Squamata
Viperidae
Hypnale
Hypnale zara

description: Hypnale zara (Gray, 1849)
(Fig. 6; Fig. 7; Table 2)
Trigonocephalus zara Gray, 1849
Holotype. BMNH 1946. 1. 19. 96 male, 303 mm SVL, “ Singapore ”, coll. “Mr Argent” (see Discussion).
Measured material. Males, 2 ex. (WHT 2198, WHT 1981, MMB, 10 XII 1995), 338 mm, 361 mm SVL; females, 5 ex. (WHT 5840, SB and KW, 20 IX 1998, WHT 5932, SB, 23 VI 2001, WHT 5935, SB, 0 2 X 1997, WHT 6087, KM and AS, 0 9 IV 2004, WHT 6088, KM and AS, 0 9 IV 2004), 375 mm, 266 mm, 162 mm, 407 mm, 310 mm SVL, respectively, Kottawa Proposed Forest Reserve, Galle, 06º06’N, 80º20’ E, alt. 60 m. Male, 1 ex. (WHT 5835, MMB and PN, 0 4 II 2000), 262 mm SVL, Ramboda, 07º03’N, 80º42’ E, alt. 1310 m. Female, 1 ex., (WHT 5941, MMB, 10 IX 1998), 372 mm SVL, Pituwala, Elpitiya, 06º16’N, 80º12’ E, alt. 60 m. Females, 3 ex. (WHT 5854, KM and AS, 22 V 2003, WHT 5933, KM and AS, 27 V 2003, WHT 5942, KM and AS, 10 VI 2003), 388 mm, 290 mm, 277 mm SVL, respectively, Matale, 07º28N, 80º37’ E, alt. 355 m. Female, 1 ex. (WHT 5943, KM, 20 III 2003), 219 mm SVL, Galaha, 07º12’N, 80º40’ E, alt. 1000 m. Females, 4 ex. (WHT 0255.L, KMA / DG, 11 VII 1993, WHT 0255.S, KMA / DG, 11 VII 1993, WHT 1992, DG; WHT 5847, SB, 0 1 IX 1997), 323 mm, 290 mm, 242 mm, 263 mm SVL, respectively, Koskulana near Panapola, adjoining Sinharaja World Heritage Site, 06º25’N, 80º27’ E, alt. 460 m. Females, 2 ex. (WHT 5940, RW, 10 IX 1998, WHT 5934, SB and RW, 0 4 X 2001), 280 mm, 322 mm SVL, respectively Mederipitiya, adjoining Sinharaja World Heritage Site, 06º21’N, 80º29’ E, alt. 365 m. Female, 1 ex. (WHT 5956, KM, 24 IX 2003), 358 mm SVL, Gampola, 07º10’N, 80º34’ E, alt. 550 m. Male, 1 ex. (WHT 5960, KM, 25 IX 2003), 275 mm SVL; females, 8 ex. (WHT 5951, KM, 25 IX 2003, WHT 5952, KM, 25 IX 2003, WHT 5958, KM, 25 IX 2003, WHT 5959, KM, 25 IX 2003, WHT 5961, KM, 25 IX 2003, WHT 5964, KM, 25 IX 2003, WHT 5950, KM, 25 IX 2003, WHT 5963, KM, 25 IX 2003), 344 mm, 285 mm, 305 mm, 277 mm, 285 mm, 220 mm SVL, 330 mm, 165 mm respectively, Nawalapitiya, 07º03’N, 80º32’ E, alt. 610 m. Male, 1 ex. (WHT 5848, SB, KM and AS, 0 2 IX 2002), 288 mm SVL, Gannoruwa Forest Reserve, 07º17’N, 80º35’ E, alt. 684 m. Female, 1 ex., (WHT 5846, KMA, 0 7 IX 1994), 122 mm SVL, Udawattakele, 07º17’N, 80º38’ E, alt. 470 m.
Diagnosis. Hypnale zara is distinguished from its congeners by a combination of the following characters: tip of snout distinctly elevated; 10–19 minute scales form a wart-like protuberance on snout tip (Fig. 6 a, b); 18–39 heterogeneous, small scales on internasal-prefrontal region (Fig. 6 b); scales around eye 6 (supraocular + 2 postoculars + 2 preoculars + postfoveal) (Fig. 6 a); maxillary pit surrounded by 3 scales (lower preocular + postfoveal + second supralabial) (Fig. 6 a); 2 postoculars, the upper one small, the lower one reaching postfoveal; no scales between postfoveal and 3rd supralabial (Fig. 6 a); lower postocular, 1st lower temporal, 4th and 5th supralabials in contact, no scale between them. Supralabials 7 or 8; lacunal scale absent; 2nd supralabial extends upward to reach loreal; costal scales keeled (Fig. 6 g); ventrals 134–157; 34– 51 scales in subcaudal series, divided; hemipenial lobes not spinous (Fig. 6 d).
Hypnale zara is distinguished from H. hypnale by having the tip of the snout distinctly elevated (vs snout tip not raised); possessing (vs lacking) a wart-like protuberance on the snout tip; having 18–39 (vs 5–15) scales on internasal-prefrontal region; the maxillary pit surrounded by 3 (vs 4–5) scales; and the lacunal scale absent (vs present).
It is distinguished from H. nepa by having the tip of the snout distinctly elevated (vs flattened or only slightly raised); 18–39 (vs 12–25) scales on the internasal-prefrontal region; the maxillary pit surrounded by 3 (vs 4–5) scales; no (vs 1–3) scales between postfoveal and 3rd supralabial; lower postocular, 1st lower temporal, 4th and 5th supralabials in contact (vs separated by a rhomboid scale of similar size); lacunal scale absent (vs present); all costal scales keeled (vs mid-dorsal scales smooth); 134–157 (vs 122–134) ventrals; and having the hemipenial lobes not spinous (vs with large spines on the proximal two-thirds of their length).
Hypnale zara is distinguished from Hypnale sp. ‘amal’ by having the tip of the snout distinctly elevated (vs not elevated); possessing (vs lacking) a wart-like protuberance on the snout tip; having 18–39 (vs 10) scales on internasal-prefrontal region; the maxillary pit surrounded by 3 (vs 4) scales; 7 or 8 (vs 9) supralabials; the lacunal scale absent (vs present); first infralabials on either side separated from each other by a median suture (vs medially fused); and two rows of distinct, bilaterally symmetrical blotches meeting on dorsal midline (vs a distinct purple-brown paravertebral stripe about 3 scales wide extending from neck to level of vent).
Description. (Based on holotype, BMNH 1946.1.19.96.) Snout tip distinctly elevated, with 14 minute scales forming a wart-like protuberance on it. Thirteen heterogeneous scales on internasal-prefrontal region; internasals and prefrontals enlarged, somewhat displaced; internasals separated from rostral by a scaly, wartlike protuberance; internasals in contact with each other. Prefrontals 2, separated by a small scale; prefrontals separated from frontal and supraoculars by 7 small scales; upper preocular, loreal and nasal extend over canthal ridge, visible from above; rostral longer than wide, obtusely pointed, only just visible from above; nasal entire; loreal acutely pointed anteriorly, its posterior margin broad, extending dorsally across canthus; 2 preoculars; 2 postoculars, the upper one small, the lower one reaching postfoveal; eye encircled by 6 scales: 2 preoculars + supraocular + 2 postoculars and postfoveal; lacunal absent. Maxillary pit bordered by three scales: lower preocular, postfoveal and upper posterior margin of 2nd supralabial; 2nd supralabial extends upward to reach loreal; supralabials, 7, not in contact with eye; 1st supralabial extends upward to reach loreal; infralabials 8; temporals smooth, in two longitudinal rows, those on lower row greatly enlarged; numerous small scales present on post-parietal region. Mental subtriangular; a pair of chin shields present, somewhat longer than wide; infralabials 8; infralabials I, II and III in contact with chin shields. Mental and chin shields separated from each other by 1st infralabial. Gular scales in 4 median series and 6 lateral series. Rows of costal scales up to 8th ventral on right side and 7th ventral on left, 19; 17 rows thereafter (including mid-body) up to 110th ventral on either side, following which 15 rows up to anus.
Costodorsal reduction (BMNH 1946. 1. 19. 96):
4+5(8) 3+4(110)
19—————17—————15 (139)
4+5(7) 3+4(110)
Costal scales at mid-body 17; paravertebral scale row not enlarged; dorsal scale rows keeled except for lowermost lateral row, which is smooth; paired apical pits present, inconspicuous; ventrals 139; subcaudal series divided, with 44 scales; anal scale entire; 2 pairs of subanal scales. Hemipenial morphology (based on WHT 5848). Hemipenes moderately long, slender, deeply forked; spines absent (Fig. 6 d); flounces denticulate, closely spaced on either side of sulcus spermaticus; sulcus spermaticus deep, with smooth walls.
Mensural data (see also Table 2). Measurements of holotype: SVL, 303 mm; TL, 59 mm, (19.5% of SVL); HL, 29.3 mm (9.7% of SVL); HW, 11.6 mm (39.6% of HL); SL, 6.5 mm (22.2% of HL); FL, 3.2 mm (10.9% of HL); FW, 3.3 mm (11.3% of HL); PL, 5.2 mm (17.7% of HL); PW, 3.3 mm (11.3% of HL); SU, 4.3 mm (14.7% of HL); SW, 3.1 mm 10.6% of HL); SS, 2.2 mm (7.5% of HL).
Variation. Wart-like protuberance on snout comprises 10–19 small scales; 9–18 small, heterogeneous scales on internasal-prefrontal region; internasals and prefrontals smaller than frontal, distinct or indistinct, sometimes somewhat displaced; internasals broadly in contact, partially separated, or widely separated; prefrontals broadly in contact with each other, partially separated, or widely separated; prefrontals in contact with supraoculars or separated from frontal and supraoculars by 1–9 small scales; nasal entire or partially divided above level of nostril. Supralabials 7 or 8; a single specimen (WHT 6089) with 6 (right side) and 7 (left side) supralabials; 1st supralabial does not reach loreal or extend upwards towards it; infralabials 8–9; infralabials I and II or I–III in contact with chin shields; gular scales in 3–6 median series and 6–9 lateral series; lowermost 1–6 rows of costals smooth; ventrals 134–157 in males, 134–157 in females; subcaudal series divided medially, with 43–51 scales in males, 34–50 scales in females (WHT 5835 with the two proximal-most scales of subcaudal series undivided, with 46 scales in divided series); 2–4 pairs of subanal scales.
Coloration. Dorsal ground colour varies from yellowish-brown to dark brown, sometimes deep red (Somaweera, 2006: 269). Two rows of distinct sub-oval or sub-triangular blotches meet on dorsal midline, bilaterally symmetrical (especially on tail), sometimes displaced longitudinally on body (see Fig. 7 c). A dark stripe present across eye and cheek. Overall colour of venter much lighter than that of dorsum, sometimes light ash-grey.
Natural history notes. Hypnale zara was recorded only from the lowland rainforests of the island’s south-western ‘wet-zone’ quarter and the foothills of the central highlands (60–610 m a.s.l.) (Fig. 6 i): the species, which is endemic to Sri Lanka, is absent in anthropogenic habitats. Hypnale zara was found only in primary and secondary forests; it was never observed, e.g., in home gardens. These snakes are essentially nocturnal: in the daytime they take refuge under decaying logs and leaf litter on the forest floor. On rare occasions we observed H. zara on shrubs up to about 60 cm above the forest floor. Because of previous confusion with H. hypnale, part of whose range is occupied by H. zara, we are unable to comment on the notes on captive care and reproduction provided by previous authors (e.g., Henry, 1925). We found a gravid female (WHT 6087), 407 mm SVL, in Kottawa Proposed Forest Reserve on 9 April 2004, with eight fullydeveloped young (97–115 mm SVL), their yolk-sacs fully absorbed and with adult coloration. Three females from Nawalapitiya were dissected, with the following results: (WHT 5951), 334 mm SVL, contained eight unfertilized ova (6.2–8.2 × 4.4–6.1 mm); (WHT 5950), 366 mm SVL, contained five small, unpigmented embryos attached to yolk sacs (21.0–25.0 × 9.4–12.5 mm including yolk sac); (WHT 5958), 305 mm SVL contained five young (108–117 mm SVL) with their yolk sacs fully absorbed and with adult coloration.
description: Published as part of Maduwage, Kalana, Silva, Anjana, Manamendra-Arachchi, Kelum & Pethiyagoda, Rohan, 2009, A taxonomic revision of the South Asian hump-nosed pit vipers (Squamata: Viperidae: Hypnale), pp. 1-28 in Zootaxa 2232 on pages 15-19, DOI: 10.5281/zenodo.190308