Oligodon kampucheaensis, Neang, Thy, Grismer, Lee & Daltry, Jennifer C., 2012

Neang, Thy, Grismer, Lee & Daltry, Jennifer C., 2012, A new species of kukri snake (Colubridae: Oligodon Fitzinger, 1826) from the Phnom Samkos Wildlife Sanctuary, Cardamom Mountains, southwest Cambodia, Zootaxa 3388, pp. 41-55 : 44-51

Oligodon kampucheaensis sp. nov.

Figs. 1–4 ; Tables 1–5.

Holotype. CBC 01464; adult male collected by Thy Neang, Seiha Hun and Moeun Meang on 27 January 2011 at Chruk Prul stream at N 12°11’55.1”, E 103°03’35.3”, 330 m above sea level in the Phnom Samkos Wildlife Sanctuary, Cardamom Mountains, Pursat Province, southwest Cambodia.

Diagnosis. Oligodon kampucheaensis sp. nov. is distinguished from all of its congeners by the following combination of characters: MT 11; frontal and prefrontal separated; 1/1 anterior and 2/2 posterior TP; SL 8/8, 4th and 5th contacting orbit; InL 8/8; TL/SVL 0.178; DSR 15–15–15; VS 164; SC 39; anal plate undivided; deep bifurcated hemipenes, lacking papillae and spines, extending to SC 11; 17 transverse cream, black-edged bands that do not encircle body and three cream, black-edged bands on tail; no dorsal stripes, blotches or reticulated black crossbars on body; eight or nine scales long between crossbands, except for seven scales long between 5th and 6th and 10 scales long between 11th and 12th crossband; white ventrolateral spots on lateral margins of every dark brown squarish or subrectangular ventral blotch. For differential comparisons with congeners, see Comparisons section below.

Description of holotype. Adult male; head elongate, HL 14.2 mm, HW 9.1 mm, slightly flattened, HD 7.2 mm, not notably wider than neck; body robust, subcylindrical; SVL 363.2 mm; tail thick, robust, TL 64.8 mm; TL/ SVL ratio 0.178; snout, elongate, about one third of HL, SnL 4.2 mm; EN 2.7 mm; ND 3.7 mm, slightly narrower than SnL; rostral shield large, thick, in contact with first supralabial and nasal laterally and internasals posteriorly; rostral shield slightly widened, 1.3 times wider than high, posteriorly pointed and intruding into the anterior suture between internasals; internasals paired, in broad contact, 1.9 mm in width, more than twice as wide as long (0.9 mm), separated by a median suture; prefrontals large, 2.6 mm in width, 2.1 mm in length, forming butterfly shape, separated by suture; suture between internasals (0.8 mm) shorter than that between prefrontals (1.1 mm); frontal large, pentagonal, posteriormost portion pointed, contacting parietal; supraocular large, elongate, pentagonal, narrower anteriorly; parietals form heart shape; suture between parietals (3.8 mm) slightly shorter than length of frontal (4.1 mm); nasal elongate, subrectangular, vertically divided, anterior part larger, in contact with rostral shield anteriorly, 1st and 2nd SL ventrally, internasal and prefrontal dorsally, loreal posteriorly; nostrils in posterior part of anterior nasal; 1/1 moderately sized, subrectangular loreal; 1/1 vertically elongate, rectangular preocular; pupil round, ED 2.4 mm; presubocular absent; 2/2 large rectangular postoculars, lower one on right side smaller, subtriangular; 1/1 large rectangular anterior temporal; 2/2 posterior rectangular temporal, upper twice as wide as lower; SL 8/8, 1st and 2nd contacting nasal, 2nd and 3rd contacting loreal, 3rd and 4th contacting preocular, 4th and 5th contacting orbit, 7th largest; InL 8/8, 1st pair in contact, 1–4 in contact with anterior chin shield, 5th largest, touching posterior chin shield, 8th InL separated from ventral scale by four scale rows; anterior chin shield twice the length of the posterior chin shield.

Maxillary teeth: 11, in size 1<2<3<4<5<6<8<9<10<<11, all curving backward, sharp, blade-like posterior edge, diastema between 10th /11th.

Body scalation: DSR: 15–15–15; DSN measured at 12th VS; MSR measured at 83rd VS; DSV measured at 157th VS; scale reduction from 17 scale rows at 9th VS to 15 scale rows at 10th VS; eight or nine scales between crossbands, except seven scales between 5th and 6th crossband and 10 scales between 11th and 12th crossband; all dorsal scales small, subrectangular and smooth; VS 164 (excluding 1 preventral), angulate laterally; SC 53, all paired; anal undivided. Hemipenes covered by lobes, deeply bifurcated at the level of 6th SC; tip of each organ reaching SC 11 (possibly not fully everted; Fig. 2 ).

Color. In life ( Fig. 3 ), the specimen was reddish-maroon on head, dorsum, and flanks, this background color extending all the way onto edges of ventrals. It had 17 transverse cream colored, black-edged dorsal bands, extending ventrally to the first or second dorsal scale row, three cream dorsal bands edged in black on tail; scattered blackedged scales on body and tail; parts of each scale with dull reddish brown, minute speckling on a red background; creamy orange on rostral shield; part of nasals, edges of internasals and prefrontals, preoculars, 1st through 4th SL, and part of 5th SL white; a creamy crescent marking extended over frontal, and supraocular to posterior corner of eye, extending ventrally as a large indistinct creamy, oblique streak terminating at the lower margin of 8th SL; large inverted V-shape extends posteriorly, crossing the parietal and touching posterior margin of posterior temporal and downward to 6th VS; large red streak below eye on 5th and 6th SL bordered by white stripes anteriorly and posteriorly; anterior half of 8th SL red, posterior half bearing an indistinct creamy streak; white ventrolateral spots on lateral margins of every dark brown squarish or subrectangular ventral blotch (observed in life and preservative). In preservative ( Fig. 4 ), one-fifth of anterior venter is white, posterior four-fifths pinkish-white; dark brown blotches on belly, more indistinct squarish anteriorly and darker subrectangular in shape posteriorly on the lateral edges of approximately every second or third of ventral scale; posterior part of subcaudal region lacks blotches.

Natural history. The holotype of Oligodon kampucheaensis sp. nov. was found on the ground beside a dried puddle on a logging road in lowland, disturbed evergreen forest. Although most members of the genus are typically nocturnal ( Whitaker & Captain 2004; Green et al. 2010), this snake was found basking at 8:25 am during the relatively cool period of the early dry season. The air temperature was 26.3° C and relative humidity 94%.

Etymology. The specific epithet is in reference to the country Kampuchea ( Cambodia) in which the type locality is located and to which this species is presumed to be endemic.

Comparisons. Oligodon kampucheaensis sp. nov. is compared here to three tentative groups within Oligodon : the O. taeniatus group, O. cinereus group and the O. cyclurus group ( David et al. 2008a, b, 2011; Green et al. 2011; Smith 1943; Wagner 1975), most of which occur in Indochina ( Cambodia, Vietnam and Laos), and, to Southeast Asian species that are similar in color and crossbar pattern and have similar dorsal scale row numbers to the new species, although many of the latter occur outside of the Indochinese biogeographical boundaries.

Oligodon kampucheaensis sp. nov. differs from most species of Oligodon by having white ventrolateral spots on the lateral margins of every dark brown squarish or subrectangular ventral blotch. The new species is further distinguished from all other nominal species in Indochina and Southeast Asia by the following unique combination of morphological characters.

From the O. taeniatus group (Table 1), it differs in possessing DSR 15–15–15 (vs. 17–17– 15 in O. barroni (Smith, 1916) from Cambodia, Thailand and Vietnam, O. deuvei David, Vogel, & Rooijen, 2008 from Cambodia and Vietnam, O. moricei David, Vogel & Rooijen, 2008 from southern Vietnam, O. mouhoti (Boulenger, 1914) from Cambodia, Eastern Thailand and southern Vietnam and O. pseudotaeniatus David, Vogel & Rooijen, 2008 from Thailand, and vs. 19–19– 15 in O. taeniatus (Günther, 1861) from Cambodia, Thailand, southern Vietnam and Laos; having transverse cream body and caudal bands edged in black (vs. no cream bands edged in black); lacking dorsal stripes (vs. dorsal stripes present, except in O. barroni ) and lacking dorsal blotches (vs. blotched in O. barroni ), having deep bifurcated hemipenes with no papillae (vs. deep bifurcated hemipenes with large papillae in all members of the O. taeniatus group except O. moricei [unknown]).

From all species of the O. cinereus group (Table 2), O. kampucheaensis sp. nov. differs in having deeply bifurcated hemipenes (vs. non-bifurcated hemipenes). With DSR 15–15–15, the new species is separated from O. cinereus (Günther, 1864) from Cambodia, Thailand, Laos, India, Bangladesh, Myanmar, Malaysia and China, O. joynsoni (Smith, 1917) from northwestern Thailand and O. melanozonatus Wall, 1922 from India and China, all of which have DSR 17–17–15. It is distinguished from O. albocinctus (Cantor, 1839) from India, Nepal, Bangladesh, Myanmar and China which has DSR 19–17(19)–15(17) and separated from O. splendidus (Günther, 1875) from Myanmar that has DSR?–21–?. Among the O. cinereus group, O. kampucheaensis sp. nov. is superficially similar to O. inornatus (Boulenger, 1914) from Cambodia and Eastern Thailand in having DSR 15–15–15, but differs in its higher TL/SVL ratio (0.178 vs. 0.130–0.166), having transverse cream, black-edged bands (vs. a uniform, dark pattern); fewer VS (164 vs. 169–174). Oligodon kampucheaensis sp. nov. is similar to O. albocinctus in having transverse cream, black-edged bands on the body and tail and having eight or nine scales between each crossband, but differs in having the 4th and 5th SL contacting the orbit (vs. 3rd and 4th), higher SL (8 vs. 7), fewer VS (164 vs. 177–208) and white ventrolateral spots on the lateral margins of every dark brown squarish or subrectangular ventral blotch (vs. absent in O. albocinctus ). The new species also differs from O. woodmasoni (Sclater, 1891) in this group from India by having fewer DSR 15–15–15 (vs. 17), more SL (8 vs. 6), fewer VS (164 vs. 180–190) and deep bifurcated hemipenes (vs. non-bifurcated) (see Smith 1943).

Oligodon kampucheaensis sp. nov. is similar to species in the O. cyclurus group (Table 3) in its deeply bifurcated hemipenes which also lack papillae (except O. formosanus (Günther, 1972) which has papillae and spines ( Smith 1943; David et al. 2011), but differs in its markedly fewer DSR 15–15–15 (vs. [19,21,23]–[17,18,19,21]–[13,15,17]) and DSR? –17–? in O. macrurus (Angel, 1927) ; lacking reticulated black crossbars on the body, lacking solid black or dark brown dorsal blotches, having transverse cream, black-edged bands on body and tail, having 3 temporals (vs.> 4, except 3 in O. chinensis (Günther, 1864) and O. formosanus ). The new species also differs from O. kheriensis Acharji & Ray, 1936 from India and Nepal and O. juglandifer Wall, 1909 from India in its fewer DSR 15–15–15 (vs.?–19–?), higher TL/SVL (0.178 vs. 0.121–0.161 in O. kheriensis ), fewer SC (39 vs. 53–68) and more SL (8 vs. 7 in O. juglandifer ) (see Smith 1943).

Oligodon kampucheaensis sp. nov. obviously differs from O. purpurascens (Schlegel, 1837) from southern Thailand, East and West Malaysia, Singapore and Indonesia by its DSR 15–15–15 (vs. [19,21] –[19,21]–[15,17]), fewer TP (1+2 vs. 2+3 or 2+2); transverse cream, black-edged bands on body (vs. blotched) ( Taylor 1965; Tillack & Günther 2009). It differs from O. signatus (Günther, 1864) from West Malaysia, Singapore and Indonesia in having a lower TL/SVL ratio (0.178 vs. 0.222–0.328), 4th and 5th SL contacting orbit (vs. 3rd and 4th), more SL (8 vs. 7), and fewer SC (39 vs. 47–59). It differs from O. booliati Leong & Grismer, 2004 from West Malaysia in having DSR 15–15–15 (vs. 17–17–15), lower TL/SVL (0.178 vs. 0.282–0.338), 4th and 5th SL touching orbit (vs. 3rd and 4th), more SL (8 vs. 6 or 7), more VS (165 vs. 143–153) and fewer SC (39 vs. 54–60); it differs from O. cruenatus (Günther, 1868) from Myanmar and O. theobaldi (Günther, 1868) from Thailand, Myanmar and India in its fewer DSR 15–15–15 (vs. 17–17–15), fewer MT (11 vs. 14–16), having a single anal plate (vs. divided) and having deep bifurcated hemipenes (vs. non-bifurcated) ( Table 4 ).

Oligodon kampucheaensis sp. nov. can be further distinguished from O. catenatus (Blyth, 1854) from India, Myanmar, Vietnam, southern China and Laos, O. annamensis Leviton, 1953 from Vietnam, and O. eberhardti Pellegrin, 1910 from Vietnam, Laos and China, O. mcdougalli Wall, 1905 and O. planiceps (Boulenger, 1888) from Myanmar which have DSR 13–13–13 (vs. 15–15– 15 in O. kampucheansis sp. nov.). The new species also differs from O. jintakunei Pauwels, Wallach, David & Chanhome, 2002 from Thailand and O. lacroixi (Angel & Bourret, 1933) from northern Vietnam which have fused frontal and prefrontal (vs. frontal and prefrontal separated) and a divided anal plate (vs. undivided) (Table 5).

In having DSR 15–15–15, the new species is similar to O. brevicauda Günther, 1862 from India, O. hamptoni Boulenger, 1900 from northern Thailand and Myanmar, and O. pulcherrimus Werner, 1909 and O. praefrontalis Werner, 1913 from Indonesia, but is distinguished from these in having the frontal and prefrontal separated (vs. frontal and prefrontal fused) and a single anal plate (vs. divided, except in O. praefrontalis ). The new species differs from O. praefrontalis in having separated frontal and prefrontal scales (vs. frontal and prefrontal fused), fewer VS (164 vs. 193) and an undivided anal plate (vs. divided) (see Pauwels et al. 2002; Tillack & Günther 2009).

With the exception of DSR 15–15–15, O. kampucheaensis sp nov. differs from O. annulifer (Boulenger, 1893) from Brunei and Malaysia in having a lower TL/SVL ratio (0.178 vs. 227–0.247), more MT (11 vs. 7), and 4th and 5th SL touching orbit (vs. 3rd and 4th) in O. annulifer (see Tillack & Günther 2009); it is separated from O. dorsalis Gray & Harwicke, 1835 from Thailand, Myanmar, Bangladesh and Indian in lacking a vertebral stripe (vs. present), having more MT (11 vs. 6–7) and a single anal plate (vs. divided) (see Smith 1943); it is distinguished from O. erythrorhachis Wall, 1910 from India in having loreal (vs. loreal absent), having more MT (11 vs. 7–8), and having a single anal plate (vs. divided). In having deep bifurcated hemipenes, O. kampucheaensis sp. nov. clearly differs from O. melaneus Wall, 1909 , and O. nikhili Whitaker & Dattatri, 1982 , both from India, O. waandersi Bleeker, 1860 , O. petronellae Roux in De Rooij, 1917 and O. wagneri David & Vogel, 2012 , all from Indonesia, O. ornatus Van Denburgh, 1909 from Taiwan & China, and O. torquatus (Boulenger, 1888) from Myanmar which have nonbifurcated hemipenes (see Smith, 1943 and David & Vogel, 2012). Finally, O. kampucheaensis sp. nov. is distinguished from O. sublineatus Duméril, Bibron & Duméril, 1854 from Sri Lanka by having more MT (11 vs. 6–8), having a single anal plate (vs. divided) and having deep bifurcated hemipenes without spines (vs. bifurcated at tip with spines) (see Smith 1943).

Figures

FIGURE 1. Map of Cambodia, illustrating the type locality of Oligodon kampucheaensis sp. nov. from the Phnom Samkos Wildlife Sanctuary, northwestern Cardamom Mountains, Cambodia.

FIGURE 2. Preserved hemipenes of the holotype CBC 0 1464 O. kampucheaensis sp. nov. Photograph by Thy Neang.

FIGURE 3. Holotype CBC 0 1464 of O. kampucheaensis sp. nov. in life. Photograph by Thy Neang.

FIGURE 4. Preserved holotype CBC 0 1464 O. kampucheaensis sp. nov. A. dorsal and lateral; B. dorsal head; C. lateral head; D. ventral view. Photograph by Thy Neang.

Tables

TABLE 4. Comparison of morphological and color pattern characters of Oligodon. kampucheaensis sp nov. with O. purpurascens, O. signatus, O. booliati, O. cruenatus, O. theobaldi. The characters and data for other species were taken from Das (2010); David & Vogel (2012); Leong & Grismer (2004); Smith (1943); Taylor (1965); Tillack & Günther (2009); and Tweedie (1983). See Materials and Methods for abbreviations.

Species/ characters	O. kampucheaensis O. purpurascens sp. nov.	O. signatus	O. booliati	O. cruentatus	O. theobaldi
TL/SVL	0.178 0.145–0.231	0.222–0.328	0.282–0.338	0.183	0.137
TP	1+2 2+3,2+2	1+2 (1 or 3)	1+2		?
SL-Eye	4+5 4+5 (5)	3+4	2+3, 3+4	4+5	4+5
SL	8 8	7	6–7	8	8
InF	8 9	7–8	7	5	?
MT	11 9–10	7–8	?	14–16	15–16
DSN	15 19–21	15–17	17	?	?
MSR	15 19–21	15–17	17	17	17
DSV	15 15–17	15	15	?	?
VS	165 160–210	141–160	143–153	148–173	164–180
SC	39 37–60	47–59	54–60	27–40	30–42
AP	1 1	1	1	2	2
BB	20 13–23	15–20	19–22	–	–
HS	+?	?	?	–	–