The spider, bigger than a half-dollar coin when it extends it legs, has been name Trogloraptor or "cave robber" for its cave homes and spectacular, elongate claws, researchers writing in the journal ZooKeys reported.
Trogloraptor hangs beneath rudimentary webs on cave ceilings, and its extraordinary, raptorial claws suggest that they are fierce, specialized predators, although their prey and attack behavior remain unknown, researchers said.
The evolutionary features of Trogloraptor are so special it is not only a new genus and species but has been placed in an entirely new family, Trogloraptoridae.
Even in the species-rich world of insect and arachnids, the discovery of a new, previously unknown family is an historic moment, researchers said.
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