On the identification and distribution of the two‐striped night adder (Causus bilineatus) and related forms

Abstract

An examination of material of Causus bilineatus Boulenger 1905 and of its sympatric congeners from south central Africa confirms its distinctness. Comparisons of allopatric populations of C. bilineatus indicate that the variation in number of ventral and subcaudal scutes is limited and represents clines rather than splits between taxa, i.e., C. lineatus Laurent is considered a synonym of the monotyp‐ic C. bilineatus as earlier proposed. Characters are presented to help its identification, a key to the genus is constructed, and distribution maps of the six recognised species are prepared.