For decades, specimens had been kept in dusty drawers of museums in Australia and Europe that are now rewriting the history of local marsupials. A ten-year study has shown that what was considered known species of short-nosed bandicoots actually conceals two new ones — and one of them apparently vanished before scientists even had time to describe it.
These are the little brown bandicoot (Isoodon microtis) from South Australia and the New Guinea brown bandicoot (Isoodon moresbyensis). Judging by collection specimens, the former lived in the region about a century ago and went extinct without leaving a trace in the modern fauna. The latter was previously considered merely a subspecies of the northern brown bandicoot, but morphological and genetic data have confirmed its independent status.
Researchers from the Western Australian Museum, Queensland University of Technology and the South Australian Museum studied hundreds of skulls and tissue samples from collections around the world. Comparing sizes, shapes and DNA made it possible to refine the species boundaries within the genus Isoodon. As a result, it turned out that three species once lived in South Australia at the same time: the southern brown bandicoot, the newly described little brown bandicoot, and the quenda (Isoodon fusciventer).
The quenda, traditionally considered a Western Australian species, according to the new data once lived much farther east — as far as the vicinity of Adelaide, Kangaroo Island and the Nuytis Archipelago. This expands the understanding of its historical range and may soften the overall threat assessment for the species, although local populations in South Australia still need protection.
Changes in classification directly affect conservation strategies. The southern brown bandicoot, already endangered, now apparently has an even more limited range. By contrast, the wider distribution of the quenda gives hope that the species as a whole is more resilient than previously thought. Such revisions show how fragile and incomplete our picture of biodiversity is, even in well-studied regions.
The discovery of an extinct species evokes mixed feelings: joy at restoring historical truth and bitterness at the realization that a unique animal disappeared without even being named in its lifetime. At the same time, the finding of a living species in New Guinea reminds us that museums are not merely repositories of the past but true treasuries capable of changing our understanding of the present.
The work on the short-nosed bandicoots is complete, but ahead lies the study of the long-nosed ones (genus Perameles), five species of which have already gone extinct since European settlement. Further discoveries probably await in those same museum drawers.
Studying old collections helps to assess extinction risks more accurately and to direct conservation efforts where they are needed most.
