[2] They were described in 2012 by a research team consisting of arachnologists Charles Griswold, Tracy Audisio and Joel Ledford of the California Academy of Sciences.

[2] Lead researcher Griswold claimed that Trogloraptor might explain the legends of giant cave spiders in the area.

[2] However, Trogloraptor exhibits several unique features, including primitive respiratory systems, that justify its assignment to a separate family.

The family probably diverged from other spiders about 130 million years ago, which would make it another notable relict taxon from North America.

The generic name Trogloraptor means "cave robber", in reference to the spider's habitat and hooked raptorial tarsi.

Except for a single juvenile specimen recovered from the understory debris of old growth redwood forests of northwest California, none have been found outside the caves.

[2] The family Trogloraptoridae may have had a wider distribution given that redwood forests encompassed a far greater area in North America during the Pliocene (about 5 mya).

[2] Hooked tarsal claws are also present to a lesser extent in the unrelated genera Doryonychus of Tetragnathidae, Hetrogriffus of Thomisidae and Celaenia of Araneidae.

Similar to the Nelson cave spider of New Zealand (Spelungula cavernicola, a gradungulid), Trogloraptor probably dangle upside down from their webs, snatching at passing flying insects with their claws.