Brush-tailed Mulgara Dasycercus blythi

A carnivorous Australian marsupial found in the western arid zones of the continent. It digs burrows as deep as half a meter, providing protection from the extremes of climate. They are an opportunistic carnivore eating a wide range of invertebrates, frogs, reptiles, and small mammals. Beetles are one of the most common food source.

Image Credit: Unknown

But I'm getting ahead of myself. For someone who isn't a dasyuromorph disciple or other variety of Australian mammal nerd, what are mulgaras?

"Crest-tailed mulgara" on the left and "brush-tailed mulgara" on the right (Image credit: Yingyod Lapwong & Owen Lishmund)

Mulgaras (Dasycercus) are a genus of carnivorous marsupials in the family Dasyuridae, which includes Tasmanian devils, quolls and a huge variety of other smaller but equally vicious predators. A fair size as far as dasyurids go, these rat-sized mammals are specialists of arid and semi-arid environments and were previously widespread across much of inland Australia, but their distribution retreated deeper into the interior of the continent following European colonisation. One trait that sets them apart from other dasyurids is their burrowing prowess - while many dasyurid species will inhabit burrows dug by other animals, mulgaras are skilled diggers that will construct their own extensive burrow networks, complete with a main entrance and several side tunnels and pop holes.

Trying to figure out how many species of mulgara there are has always been a source of great confusion to mammal taxonomists. The first species described was Dasycercus cristicaudata back in the 1860s, followed by D. blythi and D. hillieri in the early 1900s. These two new species were synonymised with D. cristicaudata in 1988, leaving one species of mulgara. In 2000, mulgaras were split back into two species, D. cristicaudata and D. hillieri, but a 2006 study believed the species in question had been misidentified - what had been thought to be D. hillieri was actually D. cristicaudata, and what had been thought to be D. cristicaudata was actually D. blythi. Confused yet?

Dasycerus blythi (Image credit: Walter Baldwin Spencer)

Since then, the consensus has largely been that the two species of mulgara were the crest-tailed mulgara (Dasycercus cristicaudata) and the brush-tailed mulgara (D. blythi), both named after their distinctive tail shapes. However, the new paper turns this idea on its head yet again, with the most dramatic revision of Dasycercus species thus far.

Based on measurements of the teeth and skull, Newman-Martin et al. identified six different species within Dasycerus - this included D. cristicaudata and D. blythi, the previously invalidated D. hillieri, and three newly described species, D. wolleyae, D. archeri and D. marlowi. Despite this, the two previously identified living populations remained the only surviving species, with the other four being considered likely to be extinct based on their distribution. However, in one final twist, the surviving mulgaras previously considered to D. cristicaudata were found to actually be D. hillieri after all, meaning the type species of the genus is now among those believed to be extinct!

Of these species, three (D. cristicauda, D. hillieri & D. archeri) could be considered to be "crest-tailed" and two (D. blythi & D. marlowi) are "brush-tailed", while the sixth species, D. woolleyae, is usually crest-tailed but rarely brush-tailed. Given this, the appearance of the tail is no longer a distinctive characteristic of any of the species, but the authors stated that the common name could be kept for the extinct D. cristicaudata and potentially also the extant D. blythi. All other species required new common names, listed below:

Ampurta (Dasycercus hillieri)

Spinifex/brush-tailed mulgara (Dasycercus blythi)

†Crest-tailed mulgara (Dasycercus cristicaudata)

†Northern/sand mulgara (Dasycercus woolleyae)

†Southern mulgara (Dasycercus archeri)

†Little mulgara (Dasycercus marlowi)

What was previously believed to be the crest-tailed mulgara, D. cristicaudata, is now the ampurta, D. hillieri! (Image credit: Mike Letnic)

The fact that four species of mulgara are now extinct is not only inherently disheartening, but these also represent the first known dasyurid species to have disappeared in modern times. Dasyurids were previously considered to be more resilient to the impacts of invasive species and habitat degradation than other small marsupials, hence why no species had yet been lost, but the discovery of extinct mulgaras demonstrates that we are likely underestimating the impact that European invasion has had on dasyurid diversity. There may well be many other species that have already gone extinct without us even realising they existed.

Studies of dasyuromorphia! (Order name copied and pasted from Wikipedia lmao)