The fossilised remains of a giant burrowing bat that lived in New Zealand millions of years ago has been found in Central Otago.
A team of international scientists, led by the University of New South Wales (UNSW), made the discovery in ancient sediments near the town of St Bathans on New Zealand's South Island.
Burrowing bats were about three times the size of an average bat today, and are peculiar because they did not just fly.
According to scientists, they also scurried about on all fours, over the forest floor, under leaf litter and along tree branches, while foraging for both animal and plant food.
"Burrowing bats are more closely related to bats living in South America than to others in the southwest Pacific," said study first author and UNSW professor Sue Hand.
"They are related to vampire bats, ghost-faced bats, fishing and frog-eating bats, and nectar-feeding bats, and belong to a bat super-family that once spanned the southern land masses of Australia, New Zealand, South America and possibly Antarctica."
It has been named Vulcanops jennyworthyae, after the team member who found the bat fossils, Jenny Worthy, and after Vulcan, the mythological Roman god of fire and volcanoes - in reference to New Zealand's tectonic nature, but also to the historic Vulcan Hotel in the mining town St Bathans.
New Zealand's burrowing bats are also renowned for their extremely broad diet, said Hand.
"They eat insects and other invertebrates such as weta and spiders, which they catch on the wing or chase by foot. And they also regularly consume fruit, flowers and nectar.
"However, Vulcanops's specialised teeth and large size suggest it had a different diet, capable of eating even more plant food as well as small vertebrates – a diet more like some of its South American cousins," she said.
With an estimated weight of about 40 grams, the newly-found fossil bat was the biggest burrowing bat yet known. It is also the first new bat genus to be added to New Zealand's fauna in more than 150 years.
Study co-author Professor Paul Scofield of Canterbury Museum said: "These bats, along with land turtles and crocodiles, show that major groups of animals have been lost from New Zealand.
"They show that the iconic survivors of this lost fauna – the tuataras, moas, kiwi, acanthisittid wrens, and leiopelmatid frogs – evolved in a far more complex community that hitherto thought."