Lycodon truongi, Nguyen & Duong & Wood Jr. & Grismer, 2022
|
publication ID |
https://dx.doi.org/10.3897/vz.72.e82201 |
|
publication LSID |
lsid:zoobank.org:pub:E1F61203-222C-418A-A8AC-100CE72604A5 |
|
persistent identifier |
https://treatment.plazi.org/id/51567772-A632-5004-9FC9-EF7C491E7E16 |
|
treatment provided by |
|
|
scientific name |
Lycodon truongi |
| status |
sp. nov. |
Lycodon truongi sp. nov.
Figures 3 View Figure 3 , 4 View Figure 4
Suggested common name.
Truong’s wolf snake - Rắn khuyết Trư ờng.
Holotype.
Adult male (SIEZC 20249) collected on 22 December 2020 by Anh The Nguyen from Song Giang River Valley (12.37079°N, 108.83643°E; at elevation 500 m a.s.l.), Khanh Trung Commune, Khanh Vinh District, Khanh Hoa Province, Vietnam.
Diagnosis.
Lycodon truongi sp. nov. is separated from all other species of the L. rufozonatus complex by having the combination of a maximum SVL length of 700 mm; tail length 195 mm; 17-17-15 dorsal scale rows; 14 maxillary teeth; eight supralabials with the third-fifth contacting the eye; nine infralabials; one preocular; two postoculars; an elongate loreal not contacting the eye; two anterior temporals; two posterior temporals; 200 ventral scales; 91 paired subcaudal scales; a divided precloacal plate; 15 keeled vertebral scale rows from midbody to vent; uniform dark-brown to black adult head pattern; no wide light-colored nuchal-occipital collar in the adult; black dorsal ground color; 19 narrow white body bands; 13 white caudal bands; white dorsal bands on ventrolateral section of body as opposed to a reticulated pattern; anterior one-half of venter white, and posterior of venter bearing white and broken black bands. These characters are scored across all species of the L. rufozonatus complex in Table 2 View Table 2 .
Description of holotype
(Figs 3 View Figure 3 , 4 View Figure 4 ; Table 3 View Table 3 ). Head flattened slightly sloping anteriorly, distinct from the neck, HL 16.0 mm, HW 12.9 mm, HH 7.6 mm, snout somewhat elongate, SnL 6.3 mm, EN 4.8 mm; nostril oval, large, in the middle of the nasal, IND 5.6 mm; eye moderately sized, ED 2.5 mm, with a vertically elliptic pupil; rostral triangular, hardly visible from above; nasal vertically divided by a furrow along posterior margin of nostril; two square internasals, in wide, medial contact, and in contact with two large, subrectangular prefrontals posteriorly; single, azygous, subpentagonal frontal, longer than wide; two large, elongate parietals, contacted laterally by upper anterior and posterior temporals and a larger paraparietal; 1/1 wide, elongate supraocular; 1/1 small preocular, located above the posterior portion of loreal; 2/2 postoculars of similar size; 1/1 narrow, elongate loreal not entering orbit, in contact with second, third, and fourth supralabials ventrally, the prefrontal and preocular dorsally, the nasal posteriorly; 8/8 supralabials all higher than wide except last scale in the series; first and second supralabials in contact with nasal; third, fourth, and fifth, supralabials contact eye; seventh supralabial largest; two elongate anterior temporals, lower temporal the largest; two square posterior temporals of similar size; 9/9 infralabials; first pair infralabials contact medially forming a deep, medial groove; first five infralabials in contact with first pair of chinshields; anterior and posterior pair of chinshields elongate, posterior pair smaller, bearing a deep, medial grooves contiguous with groove separating first pair of infralabials; and 14 maxillary teeth.
Body elongate, somewhat laterally compressed; SVL 700 mm; TaL 195 mm; ToL 895 mm; 200 ventrals, 91 paired subcaudals; cloacal shield divided; dorsal scales in 17-17-15 rows with 15 keeled vertebral rows from midbody to vent; vertebral row not enlarged; no apical pits.
Coloration in life
(Figs 3 View Figure 3 , 4 View Figure 4 ). Head, body and tail nearly uniformly black; body bearing 19 thin white body bands extending to ventral scales, 13 thin white caudal bands encircling tail; anterior half of venter white, posterior half bearing mottled black bands; subcaudal region banded.
Etymology.
The specific epithet " Lycodon truongi " is a patronym honoring Professor Dr. Quang Truong Nguyen for his long-standing extensive contributions to the herpetology of Vietnam and his broad international collaborations.
Natural history
(Fig. 7 View Figure 7 ). The Song Giang River and its riparian habitat course through a forested river valley formed by east-west tending mountains in the northwestern portion of Khanh Hoa Province in the vicinity of the Song Giang Hydropower Station. The surrounding mountains form the northeastern slopes of Langbian Plateau and are covered with polydominant montane evergreen tropical forest that are dissected by a rich network of small streams and rivulets that feed into the Song Giang River. The specimen was found while foraging on the ground, in a relatively flat forest floor habitat surrounded by small rivulets and was taking refuge in the hollow of a tree.
Comparisons
(Table 2 View Table 2 ). Lycodon truongi sp. nov. could not be separated statistically from other species of the L. rufozonatus complex because of its small sample size (n=1). Therefore, the comparisons below are based on discrete differences some of which are color pattern characters tradionally used to separate species (Jansen et al. (2019), Luu et al. (2018, 2019), Wang et al. (2020, 2021), and Song (2021). Lycodon truongi sp. nov. differs from L. chapaensis and L. septentrionalis in the third, fourth, and fifth supralabials contacting the eye as opposed to the fourth and fifth in the former and second or third in the latter. Lycodon truongi sp. nov. differs from L. cathaya , L. chapaensis , and L. anakradaya sp. nov. by having 14 as opposed to 10-12 maxillary teeth and it differs from L. septentrionalis which has eight. Lycodon truongi sp. nov. differs from all other species of the L. rufozonatus complex by having 19 light-colored dorsal bands as opposed to 12 ( L. anakradaya sp. nov., see below) or 19-115 collectively in the remaining species. Lycodon truongi sp. nov. is further separated from L. anakradaya sp. nov. by having two as opposed to three posterior temporals. The divided cloacal shield differentiates L. truongi sp. nov. from L. banksi . L. cathaya , L. chapaensis , L. futsingensis , and L. rufozonatus . Having keeled dorsal scales differentiates it from L. cathaya and L. futsingensis . It is further separated from L. meridionalis , L. anakradaya sp. nov., and L. banksi by having 200 ventral scales versus 225-241, collectively. Its uniform black head pattern differentiates it from L. futsingensis , L. flavozonatus , L. meridionalis , and L. rufozonatus . It is separated from L. banksi , L. cathaya , L. flavozonatus , L. meridonalis , and L. rufozonatus by having the ventral portion of the white body bands form the pattern on the ventrolateral side of the body as opposed to a light-colored reticulum. It differs from L. banksi and L. anakradaya sp. nov. by having a partially banded venter as opposed to a orangish-brown or uniform grey-colored venter, respectively. It differs further from L. cathaya and L. futsingnesis by not having a wide light-colored nuchal-occipital collar. Having thin white body bands separates L. truongi sp. nov. from L. anakradaya sp. nov. and L. futsingensis which have wide body bands. Furthermore, having white body bands separates it from all other species except L. chapaensis and L. septentrionalis . Having 13 light-colored caudal bands separates it from L. anakradaya sp. nov. with 5-7 and L. chapaensis with 11 and all other species except L. cathaya and L. futsingensis which collectively have 15-35 bands.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.