Coelognathus subradiatus (Schlegel, 1837)

Kaiser, Hinrich, Carvalho, Venancio Lopes, Ceballos, Jester, Freed, Paul, Heacox, Scott, Lester, Barbara, Richards, Stephen J., Trainor, Colin R., Sanchez, Caitlin & O'Shea, Mark, 2011, The herpetofauna of Timor-Leste: a first report, ZooKeys 109, pp. 19-86 : 43-44

Coelognathus subradiatus (Schlegel, 1837) Fig. 21

Common names.

(E) Timor Racer, Lesser Sunda Racer, Lesser Sunda Trinket Snake. *(T) Samea laho (samea = snake, laho = rat).

Identification.

Coelognathus subradiatus is a slender brown racer that can be identified by a pair of black paravertebral stripes that run along its back from the rear of the head to the tail, with varying degree of completeness ( Fig. 21 ). This snake also has a short (1-3 scales) longitudinal postorbital stripe and a flat, squared tip to the snout.

Collection and natural history.

One individual was captured at night on the road leading down from Old Town Baucau into the surrounding lowlands, but still in the outskirts of the city (altitude 350 m). It had been hit by another vehicle and succumbed to its injuries shortly after collection. Coelognathus subradiatus populations in Timor-Leste may not be conspecific with those on Roti, a neighboring island to the west, or from some of the other Lesser Sunda Islands ( Monk et al. 1997).

Taxonomic comment.

We follow the taxonomy of Schulz (1996) who places the populations of Coelognathus subradiatus from Timor, the type locality according to the description of specimens by Schlegel (1873-44) collected there by Salomon Müller, in his Group 1. Of interest is that a subspecies of Coelognathus subradiatus was designated by Bethencourt Ferreira (1897) for a population from Timor, described as " Coluber melanurus (Schl.), var. timoriensis, n. var." from specimens in the Museo Bocage in Lisbon. Whereas Coluber melanurus Schlegel 1837 is currently known as Coelognathus flavolineatus , Bethencourt Ferreira’s (1897, 1898) detailed description clearly allows identification of the Lisbon specimens as Coelognathus subradiatus . We believe that in his description, and lacking a familiarity with actual specimens of Coelognathus subradiatus from other collections, ( Bethencourt Ferreira (1897, 1898) erred on the side of caution by identifying his specimens as a unique variant related to Coluber melanurus and young Coluber erythrurus ( Duméril et al. 1854). Bethencourt Ferreira’s accounts were apparently cited only twice in relation to this snake population, first by Barbour (1912) and then by de Rooij (1917). Without comment, Barbour (1912: 195) lists this population as a full species ( Elaphe timoriensis ) in his expansive table, considered an error by Schulz (1996). In an unfortunate set of circumstances, this confused situation has been compounded by the complete loss of specimens and collection data in the Museo Bocage by fire in 1978. Until the revision of Old World ratsnakes by Helfenberger (2001), this species was placed in the genus Elaphe .

Figures

Figure 21. Coelognathus subradiatus. Male from Baucau town, Baucau District (USNM 573676). Photo by Mark O'Shea.