Amateur cave explorers have found a new family of spiders in southern Oregon that scientists have dubbed

(TRA'-gla-rap-tor), or cave robber, for its fearsome front claws.

The spelunkers sent specimens to the California Academy of Sciences in San Francisco. Entomologists there say the spider -- the size of a half dollar -- evolved so distinctly that it requires its own taxonomic family -- the first new spider family from North America since 1870.

The species name, marchingtoni (mar-CHING'-tow-nee), honors Deschutes County sheriff's Deputy Neil Marchington, who led scientists to the cave outside Grants Pass.

Academy entomologist Charles Griswold says the spider spins a crude web, but scientists don't know yet what or how it eats.

The discovery is described in the online edition of the journal

.

--Associated Press