The tiny brown, eyeless beetle, Anophthalmus hitleri, was discovered in 1933 by Oscar Scheibel, a German amateur entomologist and ardent Hitler fan, and is found only in around 15 caves in central Slovenia. Initially shunned by entomologists as not being of any particular scientific interest, it has been sidelined by museums wary of exhibiting anything with such a close connection to Nazi Germany. Now, though, the 'Hitler Beetle' is so sought-after by right-wing extremists that scientists are worried it could disappear altogether.

"There is a complete run on these creatures and collectors are intruding on the beetles' natural habitat to get hold of them, " said Martin Baehr, a beetle expert at the Bavarian State Collection of Zoology. With a perfectly preserved specimen changing hands on the international insect market for as much as 2,000, poachers will apparently stop at nothing to get hold of the arthropods.

The Bavarian State Collection of Zoology, a Munich-based research organisation which houses one of the largest natural-history collections in the world, has had almost all of its 'Hitler Beetle' specimens stolen over recent years. Those that steal, say experts, are not all Nazi sympathisers, but entrepreneurs wanting to cash in on the lucrative Nazi memorabilia market where SS signet rings can fetch hundreds of pounds and a Hitler autograph is worth thousands.

Slovenian biologists have already called for the closure of the caves where Hitler beetles live to prevent amateur collectors, who flock to the area each summer, from hunting them all down.