Morphometric variation and taxonomic status of brush-tailed phascogales, Phascogale tapoatafa (Meyer, 1793) (Marsupialia : Dasyuridae)

This study details morphometric variation among the marsupial brush-tailed phascogale, Phascogale tapoatafa. The validity of phascogales from south-we stern and south-eastern Australia being classified as the single subspecies P. t. tapoatafa was questioned because of the substantial isolation of the south-west population; the northern Australian subspecies P. t. pirata was included in the inquiry. Discriminant function analysis performed on 18 sk ull characteristics (n = 50 skulls) produced separation between P. t. pirat a, south-western P. t. tapoatafa, and south-eastern P. t. tapoatafa. Separa tion was also achieved between female phascogales from Victoria and those f rom New South Wales and southern Queensland, but not between the males of t hese two populations. Univariate tests identified significant size differen ces between the groups. Field data gathered on wild P. t. tapoatafa illustr ate large size differences between phascogales of Victoria and south-wester n Australia. Phascogales from south-western Australia also exhibit a polymo rphism in teat number (6, 7 or 8 teats; n = 72) that is not observed in oth er phascogales. This isolated population may represent a distinct taxon.