Variation in the Sericornis frontalis maculatus subspecies group

Abstract

Geographical variation in the maculatus group of populations of Sericornis frontalis is discussed. The group in Western Australia is divided into the subspecies maculatus, balstoni and mellorl, the last also occurring on Eyre Peninsula. Variation is by smooth clines except in the transition between maculatus and mellori, where there are steps in the gradients of many characters, and in the transition between maculatus and balstoni, where there is a fairly sharp change in the colour of the abdomen. The contact between the yellow-bellied race maculatus and the white-bellied races balstoni and mellori is apparently secondary.