Speciation in the Colluricincla harmonica complex (Results of the Hall Expeditions No.8)

Abstract

The general conclusions to be drawn from this brief review is that the Grey Thrush complex consists of a group of allopatric variants in different stages of speciation. Much information is still lacking and the most that can be determined so far is that there is a northern brunnea group which has an interbreeding connection with an eastern harmonica group, the hybrid population linking the two having an extension into New Guinea; that harmonica is reproductively isolated from a rufiventris western group whose relationships with brunnea, to complete the circle, are uncertain. It is impossible to indicate these shades of relationship by means of conventional nomenclature. For practical purposes it seems convenient to regard the three main groups as semispecies as follows:

Colluricincla harmonica Grey Thrush
Races: harmonica, oblita, anda, strigata.

Collurincincla brunnea Brown Thrush
Races: brunnea, superciliosa.

Colluricincla rufiventris Western Thrush
Races: rufiventris, serventyi.