Homalopsis Kuhl & Hasselt, 1822

Murphy, John C., Voris, Harold K., Traub, Joshua & Cumberbatch, Christina, 2012, The masked water snakes of the genus Homalopsis Kuhl & van Hasselt, 1822 (Squamata, Serpentes, Homalopsidae), with the description of a new species, Zootaxa 3208, pp. 1-26 : 4

Homalopsis Kuhl & Hasselt, 1822

Coluber Linnaeus, 1758: 217 .

Vipera Daudin 1803a: 220 .

Homalopsis Kuhl & Hasslet 1822: 101

Pythonia Blyth 1859: 279

Pythonella Theobald 1868: 66 (lapsus for Pythonia fide Williams & Wallach, 1989 )

Type species. Coluber horridus Daudin, 1803a (synonym of Coluber buccatus Linnaeus, 1758 ) by original designation.

Content. Five species: Homalopsis buccata , H. hardwickii , H. nigroventralis , H. mereljcoxi sp. nov., and H. semizonata .

Diagnosis. Homalopsis can be distinguished from all other Southeast Asian snakes by their keeled and striated scales in 33–49 rows at midbody; crescent-shaped valvular nostrils; lower labials posterior to the eye are horizontally divided; and enlarged plates (frontal and parietals) on the crown. Snakes of the genus Cerberus are the species most likely to be confused with Homalopsis ; however, Cerberus have fewer than 30 scales rows at midbody and the frontal and parietals are ‘fragmented’ into small irregular scales.

Distribution. Homalopsis ranges from Nepal (based on an anecdotal record, Zug & Mitchell 1995) and probably northeast India, eastward to Indochina and southward into the Malayan peninsula and the Indonesian Archipelago as far east as Borneo. One specimen has been reported from Makassar, Sulawesi (Rooji 1917) but De Lang &Vogel (2005) could not validate its presence on the island. Figure 5 shows the distribution of the five species recognized here. Regional works on India and Nepal rarely mention the presence of Homalopsis . Neither Ahmed et al. (2009) nor Whitaker & Captain (2004) mention the species in India and only Schleich & Kastle (2002) report it from Nepal, and their account is based solely upon the Zug & Mitchell (1995) comment.

Figures

FIGURE 5. Map summarizing the distribution of the five species of Homalopsis. Known localities for H. nigroventralis are in black, known localities for H. mereljcoxi sp. nov. are in red. The area in yellow is the area inhabited by the family Homalopsidae. Question marks mark areas that are suspected of having Homalopsis based upon anecdotal observations in the literature or museum specimens with questionable data.