Lost and found, and lost again...

The Desert Bettong is one of Australia’s most amazing, but poorly understood, marsupials. The examination of a Desert Bettong skin in the Australian Museum’s collection has resulted in a rewriting of history.

One of the great tales of Australian mammalogy is the rediscovery of the Desert Bettong, Caloprymnus campestris. In 1931 in central Australia, the Desert Bettong was rediscovered by the indefatigable H.H. Finlayson, the honorary curator of mammals at the South Australian Museum. First described by John Gould in 1843, the Desert Bettong (or Desert Rat-kangaroo) disappeared from scientific view for 88 years and was thought extinct, before Finlayson relocated a population in the far north-east of South Australia (SA). Or so we thought. A recent examination of a Desert Bettong specimen in the collection of the Australian Museum (AM) has revealed that it was collected between 1902 and 1905 by H.J. Hillier at Lake Killalpaninna in South Australia. Not only is this a new locality for the Desert Bettong, but it precedes Finlayson’s ‘rediscovery’ by more than 25 years.

The Desert Bettong is one of Australia’s most amazing, but most poorly known, marsupials. A small 1 kg macropod, it inhabited the deserts of the Lake Eyre Basin in north-eastern South Australia; one of the hottest, most arid and barest landscapes in Australia. Known for millennia to the local Wangkangurru people as ngudlukanta, it first came to the attention of western science in 1842, when three specimens from an unknown locality in SA were sent to John Gould in England by the Governor of South Australia, Sir George Grey. Gould recognised the specimens as a new species, which he subsequently named in 1843.

It then seemed that nothing more was heard or seen of the Desert Bettong for the next 88 years until 1931, when Lou Reese of Appamunna Station in north eastern SA sent a skin and skull to H.H. Finlayson. Confirming the skin and skull to be a Desert Bettong, Finlayson immediately mounted an expedition to the region, resulting in the rediscovery of the Desert Bettong population at Koonchera Dune, SA in December 1931. Additional specimens were collected from the Ooroowillanie-Mulka area, SA between 1932 and 1935, but these were the last! Subsequently, the Desert Bettong has not been relocated and is now believed to be extinct – most likely a victim of predation by feral cats and the introduced Red Fox. All that remains of the remarkable Desert Bettong are 25 specimens in natural history museums across Australia and in two overseas institutions. But these specimens still have stories to tell.

In September 2018, we examined the Australian Museum’s only Desert Bettong specimen, a flat skin of an adult male. The specimen carries two registration tags; one from the BMNH (now Natural History Museum, London) and a more recent AM tag (registration number M.21674). The specimen came to the AM as part of an exchange with the BMNH in 1990. The original BMNH tag is not dated and notes that the specimen was unregistered, but records the collector as ‘H.J. Hillier, Esq.’ and the locality as ‘Killipanima, E. Lake Eyre, S. Australia’. ‘Killipanima’ appears to be a misspelling of ‘Killalpaninna’; this was a former Lutherian mission on the southern shore of Lake Killalpaninna, an overflow lake on Cooper Creek in north eastern South Australia, approximately 80 km east of Lake Eyre. This represents a new locality for the Desert Bettong and is the most southerly confirmed locality known for the species

Although the AM specimen carries no collection date, because it was collected by Henry (‘Harry’) James Hillier, we can conclude it was collected between 1902 and 1905 during the period that Hillier served as English teacher at the mission school at Killalpaninna. Hillier came to Killalpaninna from England seeking a warm dry climate for his health. Whilst at the Killalpaninna mission, Hillier was an amateur collector of natural history specimens many of which were sent to the BMNH or Australian museums.

It appears then that Hillier unknowingly rediscovered the Desert Bettong at least 26 years earlier than Finlayson, and this knowledge has been hidden in plain sight until recently. This is another salient lesson in how valuable museum’s collections are in discovering – and rediscovering – species.

Dr Mark Eldridge, Principal Research Scientist, Australian Museum Research Institute

Dr Sandy Ingleby, Collection Manager, Mammals, Australian Museum Research Institute

Associate Professor Karl Vernes, Ecosystem Management, University of New England, Armidale