Scientists have identified a new species of nectar-feeding bat that had lain in museum collections for over a century.

The discovery of L. inexpectata was the most ‘eureka’ moment in my whole life

Individuals of the new Brazilian bat, Lonchophylla inexpectata, had been mislabeled as a different species, Lonchophylla mordax – commonly known as Goldman’s nectar bat – since the first specimens were captured by taxonomists at the beginning of the 20th Century.

The species name means “unexpected”, reflecting the researchers’ surprise at their discovery.

It is unusual for a new species to be discovered in museum collections of such long shelf life, according to study leader Dr Ricardo Moratelli from the Oswaldo Cruz Foundation in Rio de Janeiro, Brazil.

The new bat sports distinctively pale greyish-white fur on its abdomen and throat.

And the scientists found differences in dental and skull morphology compared with other Lonchopylla species, after carrying out detailed morphological comparisons and statistical analyses.

Dr Moratelli had been trying to identify Lonchophylla specimens kept at the Smithsonian Institution’s National Museum of Natural History in Washington, US, when he noticed some preserved Goldman’s nectar bats had pale venter – or underside – fur, while others had brown fur. This led him to carry out further studies and eventually confirm he had a new species in his hands.

“The discovery of L. inexpectata was the most ‘eureka’ moment in my whole life,” he says.

Dr Moratelli and fellow researcher Dr Daniela Dias record the new species in the journal ZooKeys.

The misidentified Lonchophylla inexpectata specimens date as far back as 1908, and have been stored in museums in Brazil and the US. The team used one well-preserved bat, collected in Bahia, Brazil, in January 1908 as their holotype (the example specimen on which a species description is based). Several more misidentified individuals were collected in 1914, and in the 1970s.

The Lonchophylla inexpectata specimens were captured in the Caatinga, a dry forest environment, of north-east Brazil. The bat continues to live there today, where it has long been mistaken for the Goldman’s nectar bat, according to the team.

However Dr Moratelli added he did not have the chance to record any in the wild as part of the study.

The new bat is thought to occupy a different, but adjacent habitat, to Goldman’s nectar bats, and another bat in the genus – Dekeyser’s nectar bat (Lonchophylla dekeyseri) – which has pale fur but other morphological differences compared with the newly described mammal.

The discovery raises concern over the conservation status of the Goldman’s nectar bat, which is currently listed as “Least Concern” on the IUCN (International Union for Conservation of Nature) Red List of Threatened Species.

Researchers believe this species may actually be restricted to a small area where the Atlantic Forest and Caatinga meet in north-eastern Brazil, and could be more threatened than previously thought.

“The region has been severely modified by human activities,” explains Dr Moratelli.

The bat represents the thirteenth species in the Lonchophylla genus, all of which live in the Neotropics and feed on nectar.

Bats are important mammalian pollinators, typically feeding on the nectar of large, pale flowers that open at night and that give off a fruity smell. Some species have adapted exceptionally long tongues to reach inside deep petals to extract the liquid treat.

Lonchophylla inexpectata is the seventh bat species Dr Moratelli has found by examining museum specimens.

Last year for example, he, along with a colleague, discovered a gold-coloured mouse-eared bat from Bolivia, Myotis midastactus, which has distinctive woolly, bright, yellow fur and had been similarly mislabelled and stored away.

The latest discovery highlights the surprising secrets decades-old biological museum collections can yield.

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