Taxonomic review of the genus Dasycercus (Dasyuromorphia: Dasyuridae) using modern and subfossil material; and the description of three new species

The genus Dasycercus (Dasyuridae: Dasyuromorphia) has a long and ongoing history of taxonomic uncertainty. Currently two species are recognized: Dasycercus cristicauda and Dasycercus blythi, with the previously named Dasycercus hillieri considered a junior synonym of D. cristicauda. This investigation integrates modern, historical and subfossil material from across Australia to provide the most comprehensive review of the genus to date. Cranial and dental morphological characters that enable phylogenetic and morphometric analysis of taxa are established. Linear discriminant analysis (LDA) and principal component analysis (PCA) of craniodental measurements, including from the type specimens of named taxa (D. cristicauda, D. hillieri and D. blythi), are used to assess the validity of each taxon. The results confirm the validity of D. cristicauda and D. blythi as species, but also reconfirm the validity of D. hillieri. As a result, much of the modern ‘D. cristicauda’ material is reassigned to D. hillieri. Three new taxa are proposed: Dasycercus woolleyae sp. nov., Dasycercus archeri sp. nov. and Dasycercus marlowi sp. nov. These six Dasycercus species are distributed across Australia’s arid zone and beyond. Based on prior investigations and the results of this taxonomic review, it is likely that only D. hillieri and D. blythi are extant. The identification of four likely extinct taxa marks the first recorded instance of modern extinction within the family Dasyuridae.