The Herpetological Journal

pp. 1-20

Authors: John D. Scanlon

Abstract: The genus Cacophis, comprising four species endemic to eastern Australia, is uniquely derived among terrestrial Australasian elapid snakes in the temporal scale pattern, presence of a relatively high and narrow dorsal crest ('choanal process') on the palatine bone, and presence of keeled supra-anal scales in adult males. Recent analyses based on morphology and genetics do not completely resolve relationships among Australasian elapids, but support relationships of Cacophis with the (Furino, Glyphodon) and (Aspidomorphus, Demansia) clades, which are adopted here as outgroups for intrageneric analysis. Within Cacophis, morphoclines in size, head scalation, tooth numbers and colour patterns indicate that C. squamulosus is the sister-group to the remaining three species; among the latter, there is conflicting evidence for both (harriettae, krejftii) and (churchilli, krejftii) clades, but the latter alternative has greater support. Revised diagnoses are given for the genus and included clades, and a simple phylogeographic model proposed.

Keywords: Hydrophiinae, morphology, skull, head scales, colour patterns, behaviour, phylogeography