Systematic Status of the Colubrid Snake, Leptodeira discolor Gunther by Duellman

At the time of completing my study of the genus _Leptodeira_ (1958) I had seen no specimens of _Leptodeira discolor_, a species described by Günther in 1860 and subsequently referred to the genus _Hypsiglena_ by Cope (1887), Boulenger (1894), and Mocquard (1908), and to the genus _Pseudoleptodeira_ by Taylor (1938). Günther’s description was based on two syntypes (British Museum of Natural History numbers 1946.1.23.67 and 68) collected in Oaxaca, México, by Auguste Sallé. Information concerning the scutellation and coloration of the syntypes was provided by J. C. Battersby; in my revisionary study (_op. cit._) this information was included in a short discussion of the species, which was referred to _incerta sedis_ until specimens could be examined and the relationships of the species determined.

Through the courtesy of John M. Legler of the Museum of Natural History, University of Kansas, I have been able to study a specimen of _Leptodeira discolor_ obtained six miles southeast of Tamazulápam, Oaxaca, México, by J. R. Alcorn on June 22, 1955. Superficial examination of the external characters of this snake shows a striking resemblance to _Leptodeira_. The specimen has a vertical pupil, divided anal, 21 scale rows, and two apical pits. The enlarged posterior maxillary teeth are without a trace of a groove. Examination of the hemipenis revealed that the organ was bifurcate and had a forked sulcus; these penial characteristics are diagnostic of the subfamily Xenodontinae and not the subfamily Colubrinae that includes the genera _Hypsiglena_ and _Leptodeira_.

Examination of all available xenodontine genera indicates that this snake belongs to a heretofore unnamed genus. In recognition of the mental torment customarily suffered by workers attempting to ascertain the relationships of the many genera of colubrid snakes, I propose the generic name