New animal species are discovered and recorded by taxonomists every year – from miniscule invertebrates to mammals to previously unknown dinosaurs. Scientists at the Californian Academy of Sciences alone for example, described a total of 211 new organisms during 2014.

Most new species are recorded in the field, but some specimens are hidden away under scientists’ noses – in museum collections. Sometimes they have been misidentified, or even forgotten. But biological collections, which can be decades or even centuries old, can yield surprising secrets.

Here are five extraordinary new species that have been discovered in museums in recent years.

1. The olinguito

The discovery of a carnivorous mammal that’s new to science is extremely rare, but in 2013 a team in the US unveiled an unusual new species, the olinguito, described as a cross between a cat and a teddy bear.

The odd creature was the first new carnivore to be discovered in the western hemisphere in 35 years.

Specimens of the mammals had been stored away in several museum collections, and many had been mistaken for another species belonging to the Procyonidae family, the olingo. The research team analysed the fur and bones of the specimens using DNA testing, to confirm their suspicion that they had a new species on their hands.

In the wild these enigmatic animals, which measure around 35cm (14 inches) in length and sport thick orange-brown fur, are found living high in the cloud forests of the Andes, in Ecuador and Columbia.

2. An ancient megamouth

A previously unknown ancient shark species called Megachasma applegatei was described in 2014 after scientists analysed 67 fossilised teeth that had been dug up during the 60s and 70s in the US, and subsequently preserved in museum collections.

Palaeontologists had suspected for years that the teeth might belong to an ancient relative of the rarely seen living megamouth shark Megachasma pelagios, a filter feeder that was first recorded as recently as 1976, when it was accidentally hauled up by a navy boat off the coast of Hawaii.

The study, published in 2014 in the Journal of Vertebrate Palaeontology, solved a decades-old mystery and provided an understanding of the lineage of the modern, mysterious megamouth.

3. A golden bat

A golden bat found only in Bolivia was described as new species Myotis midastactus in August 2014. Specimens of the bat, with characteristic bright golden-yellow, very short and woolly fur, had been kept in a number of museums but had previously been classified as another bat found in South America – Myotis simus.

The bat’s bright colouration, which is unique among New World Myotis species, earned the mammal its new name midastactus, after the Greek legend of King Midas and his golden touch.

Researcher Ricardo Moratelli who made the discovery, says museum collections are underrated by many researchers, who “do not realise that biological collections are the potential home of many new species that are only awaiting to be discovered and described”.

Dr Moratelli has found four new species within museum collections, including Myotis lavali, which was stored for 111 years before it was formally described as a new species.

4. Pentaceratops

For 75 years the fossilised bones of Pentaceratops aquilonius lay overlooked in a Canadian museum. They had been wrongly classified when they were first dug up. And it wasn’t until November 2014 that biologist Nick Longrich from the University of Bath in the UK revealed that the ancient bones in fact belonged to a previously unkown species of horned dinosaur.

The plant-eating beast was a smaller relative of Triceratops was about the size of a buffalo and roamed western North America around 75 million years ago at the end of the Cretaceous Period.

The findings provided new evidence that there may have been many more dinosaur species living closely together in the region than previously thought. According to Dr Longrich, “The distribution of dinosaur species was very different from the patterns seen in living mammals. In living mammals, there tend to be relatively few large species, and they have large ranges. With Cretaceous dinosaurs, we see a lot of large species in a single habitat.”

5. The zebra-like ringlet

Collected 90 years ago, the zebra-like ringlet butterfly lay in London's Natural History Museum’s huge butterfly and moth collection, containing around 9 million specimens, until curator Blanca Huertas identified the previously unrecognised specimen in 2011.

The ringlet Splendeuptychia mercedes is endemic to Peru, where it was collected and brought back to the museum in 1903. The striking tropical insect, which has large stripes on its wings, was discovered after Dr Huertas identified another butterfly new to science in the collection in 2009 – the Magdalena Valley ringlet, Splendeuptychia ackeryi – which is distinctive for its unusual hairy mouth.

Top image by Mark Gurney

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