A Big-eared Bat has been rediscovered in Papua New Guinea after more than a century.

In the lowland jungles of Papua New Guinea, some 200 km down the coast east of Port Moresby, two research students from the University of Queensland got a pleasant surprise when they made a routine inspection of their bat trap one morning in July, 2012. Catherine (Cat) Hughes and Julie Broken-Bow removed a cute, mysterious insectivorous bat with long ears.

They could not have known at the time, but they had just made a momentous discovery. In November, 1890, the Italian biologist Dr Lamberto Loria was collecting mammal specimens 120 km further west, at the coastal village of Kamali. Loria collected a series of strange long-eared bats that were later recognized as a new genus and species, named Pharotis imogene in 1914 – the New Guinea Big-eared Bat. This species had never been captured since and was suspected to be extinct.

Taking voucher specimens of mammals is unfortunately out of fashion, but to their great credit, Cat and Julie decided to pickle their mystery bat, and the specimen was lodged with the Papua New Guinea National Museum.

In March this year, the specimen was sent to the Australian Museum through the efforts of the Mammal Section, and the co-operation of Jim Anamiato and Bulisa Iova (PNG Museum) and Steve Hamilton (mammalogist), where I was able to determine that it was the New Guinea Big-eared Bat, and therefore the first record for some 120 years. Last century, I completed a PhD on long-eared bats and I still have something of an obsession with long-eared bat species taxonomy, so I was over the moon when the specimen arrived!

There were good reasons why Cat and Julie were not certain of the initial identification of this bat. Despite more than a century of biological exploration by researchers from around the globe, a great deal remains to be learnt about even basic aspects of the bat fauna of Papua New Guinea, such as the number of species that exist and their geographic distribution, let alone their ecological requirements. Although large numbers of bats have been collected over the decades, species of long-eared bat (and there are five in PNG) are very infrequently collected and poorly described.

Using field guides and the scientific literature, they had narrowed it down to two possibilities: either the Small-toothed Nyctophilus Nyctophilus microdon, or a Pharotis. The Small-toothed Nyctophilus was only known from high montane regions, but you never know where it might pop up, given the dearth of understanding of these bats. If it was a Pharotis, it could easily have been a new species, not P. imogene. The biggest challenge was that the descriptive information available of these species in the literature was too poor to enable Cat and Julie to make an identification. This required detailed comparisons with museum specimens.

Fortunately, the Australian Museum collection contains a comprehensive series of all New Guinean long-eared bat species, including a specimen originally collected by Loria, - one of only six in world museums - and sent to the Australian Museum in 1914 by Oldfield Thomas when he named Pharotis imogene.

Confirmation of the rediscovery of the New Guinea Big-eared Bat highlights the vital need to retain voucher specimens in mammal surveys. There is a frequent misconception that modern DNA analyses negate any scientific justification for retaining vouchers but in some situations vouchers are essential. If Cat and Julie had taken photographs and released the bat, we could determine from the photos that it was a Pharotis, but not whether it was a new species or not, because many species are distinguished mainly from skull and dental differences. Had they taken tissue samples and pics and molecular analyses had determined that it was a new species of Pharotis, we would have no idea of how to distinguish live animals, and there would be nothing to put in the next field guide to bats! More animals would need to be captured, but if the species turns out to be rare or difficult to capture – who knows when will that be?

More information: