Conservation units and phylogeographic structure of an arboreal marsupial, the yellow-bellied glider (Petaurus australis)

Abstract

Subspecific status has often been used as a surrogate for conservation unit, but does not always reflect intraspecific lineages with different evolutionary histories. One contentious case of subspecific classification occurs in the yellow-bellied glider (Petaurus australis), a marsupial species showing considerable decline in population size and requiring conservation management. Our aim was to assess the current subspecific status of populations and define units of conservation using a combination of phylogeographical analyses of mitochondrial DNA and morphological analyses. Analyses of the mitochondrial ND4 gene provided evidence for significant phylogeographic structure within P. australis. Isolated populations in north Queensland (NQ) and Victoria/South Australia were genetically distinct from populations in New South Wales and southern Queensland. Morphological analyses provided little evidence for discrimination of populations, although NQ specimens were generally smaller in size than southern forms. Our analyses do not support the classification of subspecies P. a. reginae for the original type specimen from southern Queensland. Taking into account other behavioural and ecological data, and the disjunct distribution of NQ populations from southern populations, we propose that the NQ population represents a distinct Evolutionarily Significant Unit, a lineage showing highly restricted gene flow from the rest of the species.