GRANTS PASS, Ore. (AP) — Amateur cave explorers have found a new family of spiders in Southern Oregon, which scientists have dubbed Trogloraptor — 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 — honors Douglas County sheriff’s Deputy Dave 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 Zookeys.