Biogeography of the Acacia victoriae, pyrifolia and murrayana species groups in arid Australia

Abstract

A molecular phylogeny of all extant species (21) in two clades of phyllodinous acacias, including the Acacia victoriae, A. pyrifolia and A. murrayana groups, is the basis of a paralogy-free subtree analysis of historical relationships of geographic areas in arid and semi-arid Australia. These clades are in a relatively basal position within Acacia subgenus Phyllodineae. Sister taxa generally show vicariant (allopatric) patterns. The summary area cladogram indicates that the earliest regions to differentiate were Arnhem and the North-West semi-arid region (including Dampierland, Ord-Victoria Plains and Tanami), relative to the other regions occupied by these acacias. In arid central Australia..