White-footed dunnarts (Sminthopsis leucopus) in Queensland's Wet Tropics, with the description of a new subspecies

Abstract

A population of white-footed dunnarts (Sminthopsis leucopus) occurs in the Wet Tropics bioregion of tropical north Queensland, Australia separated by about 1800 km from conspecifics in temperate New South Wales, Victoria and Tasmania. We conducted targeted surveys for S. leucopus in north-east Queensland and obtained new records, including the first reported capture of the species in Queensland in 18 years. We assessed the genetic and morphological divergence of the north Queensland population against New South Wales, Victorian and Tasmanian S. leucopus, in conjunction with distribution and habitat differences, to assess whether this isolate should be described as a distinct taxon. Sequencing of the mitochondrial Cytochrome b gene revealed genetic divergence estimates of 2.3-2.8% and 4.3-4.8% between the north Queensland population and S. l. ferruginifrons (Victoria) and S. l. leucopus (Tasmania) respectively. Based on genetic divergence, cranial morphology, differences in habitat, and geographical isolation, we describe the north Queensland population as a new subspecies of Sminthopsis leucopus. We suggest a conservation classification of Endangered given its small distribution, apparent low density, tropical upland location and potential threats, especially related to climate change.