Lycodon subcinctus F. Boie, 1827

Nguyen, Tan Van, David, Patrick & Vogel, Gernot, 2025, Designation of a Neotype for Lycodon subcinctus F. Boie, 1827 (Squamata: Serpentes: Colubridae), Zootaxa 5647 (2), pp. 196-200 : 197-199

Lycodon subcinctus F. Boie, 1827

Lycodon subcinctus F. Boie, 1827 : colum 551

— Neotype by present designation: NHMUK 1860.3.19.1307 (holotype of Lycodon platurinus Cantor, 1847 ). Type locality by virtue of neotype designation: “Pinang” now Penang Island (Pulau Pinang), State of Penang, Malaysia .

Lycodon platurinus Cantor, 1847: 69

— Holotype: NHMUK 1860.3.19.1307 . Type locality: Pinang now Penang Island, Penang State, Malaysia .

Elapoides annulatus Sauvage, 1884: 144

— Syntypes: MNHN-RA-1884.0120–0121 . Type locality: Sumatra Island, Indonesia.

Lycodon suratensis Nutphand, 1986: 157–158

— Neotype: RBINS 2610 (formerly RBINS 17036 ) designated by Pauwels et al. (2006). Type locality by virtue of neotype designation: Thung Song, Nakhon Si Thammarat Province, Thailand; type locality: Surat Thani Province, Thailand.

Description of the neotype of Lycodon subcinctus ( Figure 1 ). After 170 years in preservative, specimen NHMUK 1860.3.19.1307 (adult female) remains in good condition. The body is slender, with a long tail that gradually tapers to a blunt, enlarged terminal scute. The head is oblong, longer than wide, slightly flattened, and moderately distinct from the neck. The snout is elongated, projecting beyond the lower jaw, rounded in dorsal view, and truncate with a slight depression in lateral profile, featuring a weak canthus rostralis . The nostrils are large, positioned dorsolaterally, and round. The eyes are medium-sized, with an elliptical and slightly vertically orientated pupil.

Measurements. Snout-vent length 824 mm; tail length 179 mm; total length 1,003 mm; tail length/total length ratio 0.178. Head length (from tip of snout to posterior margin of jaws) 26.42 mm; head width (at widest point) 15.49 mm; eye diameter (horizontal diameter) 3.35 mm; eye-snout distance (from tip of snout to anterior margin of eye) 4.56 mm; eyenostril distance (from anterior margin of eye to midpoint of nostril) 2.79 mm.

Body scalation. Dorsal scale rows 17-17-15; dorsal scale rows smooth anteriorly, remaining scale rows feebly keeled at midbody and posteriorly, except for the outermost row, which is smooth; scales on the vertebral row not enlarged, no apical pits; ventral scales 217 (vs. 221 in Cantor 1847), preceded by two preventrals, laterally angulate; subcaudals 73 (vs. 74 in Cantor 1847), paired and laterally angulate; and a cloacal plate divided.

Head scalation. Rostral wider than high, barely visible from above, posterior suture not projecting into the internasal region, forming a straight angle when viewed in dorsal profile; nasal longer than high, partially divided by a small suture above the nostril; posterior half of nasal pentagonal, slightly larger than anterior nasal; nasal surrounded by the first two supralabials, loreal, prefrontal, internasal, and rostral; internasals paired, anterior sutures slightly concave in dorsal profile, in contact with rostral, nasal, and prefrontal; each internasal wider than long; prefrontals paired, approximately twice as long as internasals, subrectangular, each scale slightly longer than frontal; each prefrontal slightly wider than long, in contact with internasal, nasal, loreal, eye, and frontal; supraoculars paired, slightly subrectangular, longer than wide; frontal small, hexagonal, shield-shaped, slightly longer than wide, tapering posteriorly, angle formed by the posterior vertex of frontal slightly acute; parietals paired, longer than wide, and longer than frontal; loreal 1/1, slightly subrectangular, longer than high, in contact with the eye; preocular absent; subocular absent; postoculars 2/2, uppermost scale larger than lowermost; temporals 1+2; supralabials 8/8, first and second in contact with nasal, second and third in contact with loreal, third to sixth in contact with eye, seventh supralabial largest; infralabials 9/9, first pair in broad contact behind the mental, first to fourth in contact with the anterior pair of chin shields; mental subtriangular in ventral profile, wider than long; anterior chin shields longer than posterior shields; posterior chin shields in narrow contact medially, separated by skin tissue along the mental groove.

Colouration in preservation. The dorsal surface of the body is chestnut brown, slightly paler along the flanks. Two white body bands are present, each approximately 4–6 dorsal scales long on the vertebral row. The bands exhibit a smeared, patchy appearance and are slightly expanded ventrolaterally. The tail tip is slightly cream coloured. The dorsal surface of the head is dark brown, marbled pigmentation on the frontal. The supralabials are slightly cream coloured, with less pronounced dark brown speckling. A triangular blotch is present on the posterior temporals. The ventral surfaces of the head, body, and tail are cream and immaculate.

Figures

FIGURE 1. Lycodon subcinctus, specimen NHMUK 1860.3.19.1307 (neotype, adult female) in preservative. A—General dorsal view; B—General ventral view; C—Lateral view of the head, right side; D—Lateral view of the head, left side; E— Dorsal view of the head; F—Ventral view of the head. Photos by G. Vogel.