Oligodon deuvei DAVID, VOGEL & VAN ROOIJEN, 2008
Can you confirm these amateur observations of Oligodon deuvei?
|Higher Taxa||Colubridae, Colubrinae, Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes)|
|Synonym||Oligodon deuvei DAVID, VOGEL & VAN ROOIJEN 2008|
Oligodon deuvei — WALLACH et al. 2014: 496
|Distribution||Vietnam (Dong Nai Province, Ba Ria–Vung Tau), NE Thailand (Muang District, Loei Province)|
Type locality: “Arboretum de Trang Bôm”, now Arboretum of Bien Hoa, Dong Nai Province, Vietnam
|Types||Holotype: MNHN 1974.1366 (adult male). Collected by Sergent Poilane, July 1932.|
|Diagnosis||Diagnosis. A species of the genus Oligodon, characterized by (1) deeply forked hemipenes, not spinose but bearing two large papillae; (2) 17 dorsal scale rows at midbody, 15 before vent; (3) 12–14 maxillary teeth, the last two strongly enlarged; (4) anal plate single; (5) head scalation complete but presubocular absent in all available specimens but one; (6) 7 (rarely 8) supralabials; (7) 8 or 9 infralabials; (8) a conspicuous, broad vertebral stripe orange, bright rusty red or pale yellow, edged with two darker faint paravertebral stripes or with more or less numerous dark dots in the paravertebral region; (9) no dorsolateral stripe or a series of dark dots; (10) 4 or 5 major markings on upper head surface: one anterior transverse blotch across the snout, sometimes a small sagittal blotch on upper head surface, often reduced to spots, two oblique streaks, directed posteriorly downwards, and one broad nuchal, arrow-shaped; and (11) branches of the oblique central streaks not reaching the ventral scales in all examined specimens.|
This species differs from other species of the O. taeniatus-group by the combination of (1) 17 dorsal scale rows, (2) usually 7 supralabials, (3) a broad, often bright vertebral stripe not or barely edged with dark stripes, (4) no dorsolateral stripes, (5) body often strongly fasciated, and (6) usually no blotches on the tail.
Oligodon deuvei spec. nov. is quite close to O. barroni in scalation. It differs from the latter one by the combination of some morphological characters (see below), a higher mean number of maxillary teeth, the lack of large dorsal blotches and the presence of a broad vertebral stripe (vertebral stripe absent in O. barroni). Specimens with a “conspicuous yellow vertebral stripe and no dorsal spots on tail” mentioned by Smith (1943: 210) under Oligodon taeniatus sensu Günther (1864), namely with 17 DSR (Oligodon mouhoti), are referable to this species.
In our sample, 13 specimens show the orange or rusty brown vertebral stripe, four others, all large females from southern Vietnam and Laos, have a more subdued yellowish-brown stripe with darker dots. Only one specimen, the holotype, shows two blotches on the upper tail surface similar to those of Oligodon mouhoti. However, we could not find any other character to separate these two morphs and we consider the colour of the stripe to be variable. Specimens with the subdued yellowish-brown vertebral stripe are quite similar in pattern to Oligodon formosanus (Günther, 1872), but these two species are easily separated by the number of MSR (19 in O. fomosanus vs. 17), the number of ventrals and subcaudals (more than 160 and 45 respectively in O. formosanus) and different hemipenes [DAVID et al. 2008].
|Etymology||Etymology.–For his major contributions to the herpetology of Laos, this species is named in honour of Mr. Jean Deuve (1918-2008). Mr. Deuve spent about 20 years in Laos where he carried out several political and military duties and conducted researches on its wildlife, especially the snakes (Deuve, 1970).|