Trimeresurus gunaleni, Vogel & David & Abstract.-Variation, 2014

Vogel, Gernot, David, Patrick & Abstract. - Variation, Irvan Sidik, 2014, On Trimeresurus sumatranus (Raffles, 1822), with the designation of a neotype and the description of a new species of pitviper from Sumatra (Squamata: Viperidae: Crotalinae), Amphibian & Reptile Conservation 8 (2), pp. 1-29 : 6-15

Designation and Description of the Neotype of Coluber sumatranus Raffles, 1822

The designation is made on the following basis and in agreement with the following articles of the Code: (1) the neotype is designated in order to fix the status of Coluber sumatranus ( Raffles, 1822) according to its current definition in the literature, especially in regards to populations described below as a new species and of other species of the subgenus Parias (Art. 75.3.1 of the Code); (2) diagnostic characters of Coluber sumatranus for which we designate this neotype, are given below (Art. 75.3.2); (3) the neotype is designated in details below (Art. 75.3.3); (4) a holotype has never been mentioned in the literature, for example by Boulenger (1896). It could not be traced in the collections of the Natural History Museum (London), in contrast to Cox et al.’s (2012) statement, or of the Zoological Reference Collection of the National University of Singapore. For these reasons, we consider the holotype to be lost (Art. 75.3.4); (5) we select a specimen, the morphology of which i.e., scalation, pattern, and coloration, that agrees with characters provided in the original description (Art. 75.3.5); (6) as shown above, the holotype most probably originated from Bengkulu Province. We select a neotype from an area of Sumatra that encompasses Bengkulu Province (Art. 75.3.6). For these reasons, and in agreement with Art. 75.3.7 of the Code, we here designate as the neotype of Coluber sumatranus as the following specimen:

ZFMK 76340, an adult female, from “Southwestern Sumatra ” ( Fig. 1 )

Morphology and measurements

Body elongate, compressed; head elongate, relatively narrow seen from above, massive seen from the side, distinctly triangular, wide at its base, clearly distinct from the neck, flattened but thick, 1.8 times as long as wide; snout quite long, round when seen from above, strongly obliquely truncated when seen from the side, with a moderate canthus rostralis, totalling 28% of head length and 1.9 times as long as diameter of eye; a large, oval nostril piercing in the middle of nasal scale; nostril-loreal pit distance about 0.4 times the distance between the nostril and the eye; eye average, amounting for 0.6 times the distance between the lower margin of eye and upper lip border; tail, tapering and prehensile. SVL 895 mm, TaL 155 mm, TL 1,050 mm; ratio TaL / TL 0.148.

Body scalation

DSR: 21–21–15 scales, rhomboid, very weakly keeled with the exception of scales of first dorsal scale row which is smooth and not enlarged; 186 ventrals (+ two pre-ventrals); 61 subcaudals, all paired; anal entire.

Head scalation

Rostral barely visible from above, triangular, about as high as broad; nasals subrectangular, large, elongate, entirely divided by a furrow; two subrectangular, laterally elongate internasals, about 1.8 times wider than long, separated each from the other by one small scale; each internasal followed on each side by one very large scale on the snout, much larger than internasals, broader than long, separated each from the other by two longitudinal series of small scales; 2/2 canthal scales bordering the canthus rostralis between internasal and corresponding supraocular, i.e., the very large scale behind internasal followed by a small scale smaller than adjacent snout scales between the largest canthal scale and the supraoculars respectively; on each side, one elongate loreal scale between nasal and the upper preocular; 2/2 preoculars above the loreal pit, the upper one visible from above, both scales elongate and in contact with loreal; lower preocular forming the lower margin of loreal pit; 1/1 thin, elongated, crescent-like subocular; 2/2 small postoculars; 1/1 large supraocular, broad, 2.2 times as long as wide, about 1.3 times as wide as internasal, not indented by upper head scales; scales on upper snout surface much enlarged, smooth, juxtaposed, subrectangular, with four scales on a line between the scale separating the internasals and a line connecting the anterior margins of eyes; six cephalic scales on a line between supraoculars, smooth, flat, and juxtaposed; occipital scales flat, smooth; temporal scales in two or three rows, smooth, lower ones much enlarged; 9/9 SL, first SL triangular, rather short, completely separated from the nasal; second SL tall, bordering entirely the loreal pit and anteriorly in contact with nasal; third SL longest and highest, about 1.1 times longer than high, in contact on both sides with subocular; fourth SL barely shorter than third SL, in contact with the subocular; fifth SL barely shorter than fourth one, also in contact with the subocular; 10/11 infralabials, those of the first pair not longitudinally in contact, shortly separated by the apex of the mental scale, first–second IL in contact with anterior chin shields; four rows of smooth gular scales; throat shields irregularly arranged.

Coloration and pattern

The body is olive-green on third–eleventh DSR, slightly paler on the bottom of the sides; most dorsal scales distinctly edged with black producing a reticulate pattern; 46 irregular black crossbars on each side of the body, either symmetrical, forming black rings or more or less set off from each other on each side across vertebral line; scales of the first DSR and lower half of those of the second DSR pale greenish-yellow with black edges, producing a pale, diffuse ventrolateral stripe extending from the area just behind the neck up to vent; scales of the first DSR with a broad, irregular black edge on their anterior lower part. The tail is olive-green on its anterior half, with scales strongly edged with black, producing a strongly reticulate pattern, and two or three more or less distinct black crossbars anteriorly, becoming progressively rusty red, strongly reticulate with black.

The head is olive-green above and on the temporal region, with cephalic, occipital, and temporal scales strongly edged with black; on each side, another long streak extends from internasals to the posterior part of the head along the inner edge of supraoculars; two oblique black streaks on the occiput forming an inverted V, its apex pointing forward; supraoculars olive green, broadly edged with black; some other cephalic and occipital scales entirely black, so as to produce black blotches and streaks between supraoculars; upper snout surface heavily marked with pure black, producing broad edges around olive-green prefrontals and internasals; scale behind and between internasals black; black vertical and horizontal streaks on the rostral; supralabials yellowish-green, distinctly paler than upper head surface, strongly edged with black, with a broader streak at the limit between third–fourth supralabials; preoculars olive-green strongly edged with black; a black postocular streak extending from the eye to the area above the corner of the mouth on lower postocular and the upper rows of temporals. Chin and throat pale greenish-yellow; an irregular dark grey spot on each infralabials of the first pair; all infralabials edged with black on their posterior margin; gular scales below the corner of the mouth also narrowly edged with black.

The venter is pale greenish-yellow; each ventral narrowly edged with black, especially on their central part, sometimes on the whole of their posterior margin; tips of ventrals narrowly edged with black on each side, producing an irregular, zigzag-like black ventral stripe below the pale ventrolateral stripe. The tail is yellowish-green or greyish-yellow below on its anterior half, with subcaudal scales broadly edged with black producing a conspicuous reticulation, turning more or less abruptly to rusty red, strongly reticulated with black.

Diagnosis

A large species of pitviper of the genus Trimeresurus , characterized by the combination of (1) body elongate, head long and massive in adults; (2) body deep green or dark green with conspicuous, black crossbars on the sides in adults, with a broad, pale ventrolateral stripe, and without sexual dimorphism in coloration; (3) 21 (exceptionally 23) DSR at midbody; (4) first supralabial distinct from nasal scale; (5) large internasals, most usually separated by one scale, only exceptionally in contact; (6) three supralabials, third, fourth, fifth SL in contact with subocular, or fifth exceptionally separated by one scale; (7) supraoculars broad, separated by 3–7 (usually 5–6) scales; (8) tail average, with a ratio TaL/TL between 0.150 and 0.168 in males and 0.128 and 0.160 in females; (9) 175–191 VEN; (10) 54–68 SC (males: 66–71; females: 54–68); (11) eye dark grey in life, rather bronze, brown, dark greyish-brown or golden-brown in preservative; (12) supralabials and cephalic scales strongly and broadly edged with black; (13) a black postocular streak; (14) venter is yellowish-green or pale green, with each ventral narrowly edged with black posteriorly; and (15) tail green as the body on its anterior half, becoming more or less abruptly salmon, pinkish-red, or rusty-red on its posterior half, strongly and broadly reticulate with black. Characters separating Trimeresurus sumatranus from the new species and T. malcolmi are discussed below and summarized in Table 2.

Figures

Fig. 1 A-C. Trimeresurus sumatranus, ZFMK 76340, neotype of Coluber sumatranus Raffles, 1822, southwest Sumatra, Bengkulu Province, Sumatra. A. dorsal view of the body, B. ventral view of the body, C. lateral view oft the head. Photo: G. Vogel.