Distribution, habitat associations and status of the Carpentarian Pseudantechinus (Pseudantechinus mimulus, Dasyuridae)

Abstract

The Carpentarian Pseudantechinus (Pseudantechinus mimulus, Dasyuridae) is a little-known, saxicolous dasyurid marsupial from the Mount Isa Inlier bioregion in Queensland (QLD) and the Gulf Coastal bioregion in the Northern Territory (NT), Australia. A paucity of targeted survey effort across broad swathes of potentially suitable habitat means that the species' distribution and habitat associations are uncertain. This study aimed to (1) refine the contemporary distribution of P. mimulus, (2) determine the landscape and floristic variables that may predict P. mimulus presence, and (3) assess the current conservation status of P. mimulus. We conducted camera trap surveys covering 631 camera stations at 227 independent sites over 4 years for a total of 28 767 trap-nights throughout QLD and NT in known and predicted suitable habitat. Stepwise generalized linear models were used to test the effect of landscape and floristic predictors on P. mimulus presence. The species' contemporary distribution was assessed using a MAXENT species distribution model. We collated a database of 292 records of P. mimulus, including 111 recorded during this study, extending the species' known range in QLD. The proposed holotype location of the Mittiebah Range was surveyed twice during this study but P. mimulus was not recorded. Pseudantechinus mimulus had the highest probability of presence on most non-northerly aspects on metamorphic landforms. Eleven plant taxa had a significant effect on P. mimulus presence. This study provides new evidence for landscape and floristic factors that help predict the presence of P. mimulus. Our results indicate the possibility of two disjunct populations, but large swathes of potential habitat still require additional effort to determine the species' true distribution. Our estimate for area of occupancy partially satisfies a threatened species listing; however, more focused research on population dynamics, trends in habitat quality, and landscape-scale threats is necessary.