A zoologist has published a paper announcing a newly discovered eyeless species of the huntsman spider.

Part of the Sinopoda genus of huntsman spiders, the new species -- named Sinopoda scurion -- was spotted in Laos by Senckenberg Research Institute zoologist Peter Jäger, who has been studying the country's arachnids since 2003.

The Sinopoda scurion -- with a relatively small leg span (compared to other huntsman species) of only six centimetres -- was discovered in a cave 100km from the huge Xe Bang Fair river cave and it is thought that the cave-dweller lost its eyes after adapting to its gloomy surrounds. In the same location Jäger, who first discovered the Sinopada genus in 1999, located eight other new species with unusually small sets of two, four and six eyes each.


The regular huntsman, known for its speedy attacks on prey, is an eight-eyed spider and, although it is noted they do not have the best eyesight, their two rows of four eyes each are pretty distinctive characteristics.

However in Laos, like the cave crabs and cave crayfish found in the region, the spiders have not only adapted to their dark habitats by losing their sight, they have also lost their pigmentation. The usually dark-haired genus was found to be white-haired and transparent.

It has been suggested that cave-dwelling creatures that evolve without eyes do so to allow for conservation of energy, using their antennae and chemical touch receptors to hunt instead. However it is not known for sure why this extreme regression/evolution occurs.

Since the nine species were uncovered in the same cave district, further research may uncover clues as to how the spiders evolved, seemingly decreasing the eye count in sets of two until the completely eyeless scurion came to be.

Only one other eyeless spider species has ever been uncovered, the Kauai cave wolf spider (Adelocosa anops). The normally large-eyed wolf spider lost its eyes after living in a series of Hawaiian caves. The endangered species hunts by sensing chemical compounds in the earth.