New species of butterfly discovered by Andes expedition

A team of explorers led by scientists from the Natural History Museum in London has discovered an entirely new species of butterfly in South America.

The medium-sized, coffee-coloured insect with eyespots on its hind wings was discovered during the first manned exploration of a remote section on the northern tip of the Andes mountain range.

Idioneurula donegani was hailed as "an amazing discovery" by Blanca Huertas, the butterfly curator at the Natural History Museum, who led the expedition to the peaks of Colombia's Serrania de los Yariguies range.

"Discovery of unseen species of insect are more common than with many other types of animal," she said. "But for any biologist it's exhilarating to find an entirely new species especially one that survives in environments where you wouldn't expect to find them."

Speaking to The Independent yesterday, Ms Huertes refused to be drawn on whether another apparently new species of insect her team discovered on the expedition was also a butterfly. "Further tests have to be carried out before we can be certain that we have another species of insect as well," she said. "But I'm hopeful." If, following examination, the second specimen is also found to constitute an entirely new species of butterfly, the twin find will signal a major breakthrough in scientific understanding of the winged creatures worldwide.

"What's so fabulous about this discovery is that we would never have imagined butterflies could survive at this sort of altitude," said Ms Huertes. "Obviously when you enter unseen areas you have hopes of making exciting discoveries, but this surpasses our expectations. It means butterflies can be far more resilient and adaptable than we might have previously thought."

Although the terrain is filled with ferns, orchids and palms, it was thought to be highly unlikely that butterflies could thrive that far above sea-level.

There are more than 20,000 known species of butterfly, 40 per cent of which live in South America. The most recent discovery is not found anywhere else in the world.

The discoveries came during an expedition by an Anglo-Colombian team to the remotest heights of the Andes Mountains an area thought never to have been visited by humans before. After being taken by helicopter to an isolated peak more than 3,000m high, the team trekked through difficult conditions for more than a week.

The survey of the remote area led instantly to the creation of a national park by the Colombian government, which has come under sustained pressure in recent years from environmental groups that are concerned by the effects of rapid industrialisation on threatened species in the region.

"Butterflies and other insects have been in great danger throughout the continent," said Ms Huertes. "The cattle and crop farming that's been driving South America's agricultural growth has also been threatening to drive some species off the map."

Last year, the same Anglo-Colombian team, also led by Ms Huertes, was responsible for the discovery of the Yariguies brush finch, a fist-sized, multi-coloured bird named after the Indian tribe that once inhabited that area.

The announcement of their latest discovery comes only days after scientists in New Guinea announced the discovery of two mammalian species. A giant rat five times the size of its common cousin, and a pygmy possum thought to be one of the world's smallest marsupials were both found in a region long described by scientists as a "lost world".