A bat normally found on the Continent has been discovered in the UK for the first time, experts said today.
A male Geoffroy's bat, typically found in relatively open areas of habitat such as olive groves, woodland edge and scrub in Europe, was identified by an ecologist conducting bat surveys on National Trust land in West Sussex.
The discovery raises the possibility that the species could be moving in from Europe as the climate warms, conservationists said.
The Geoffroy's bat (Myotis emarginatus) is a small species that weighs between six and nine grams and has woolly fur with a fox-like red tint.
Consultant ecologist and bat specialist Daniel Whitby, who made the discovery, said: "It was a real surprise to catch this bat.
"Geoffroy's bat is nicknamed the notch-eared bat because it has a distinctive notch in the top part of its ear; with this, along with with other identification features, I quickly realised what an interesting bat I was holding."
He said there were 17 bat species known to be breeding in the UK, making up a third of the country's native mammals, but relatively little was known about them.
He added: "This is the second new species recorded in the UK in the past few years after Alcathoe's bat was also discovered in Sussex and through research we are slowly learning about the habitats of these fascinating but misunderstood creatures."
National Trust conservation adviser Crispin Scott said news the bat had been found on the South Downs was exciting.
"We do get a few vagrants that might get blown across the Channel in winter storms, but this was a bit of a surprise.
"It is possible the species might be moving north as the climate warms, and we do expect to see more of this in the future."
Geoffroy's bat, like all other bats, are a protected species.