A team of scientists and cave conservationists discovered a large, unique spider in caves and forests of the Pacific Northwest. Trogloraptor (or "cave robber") is named for its cave home and its spectacular, elongate claws. The spider represents not only a new genus and species, but also a new family (Trogloraptoridae).
Trogloraptor hangs from rudimentary webs beneath cave ceilings. It is about four centimeters wide (about 1.6 inches) when its legs are extended, which is larger than the size of a half-dollar coin. Their raptorial claws (pictured below) suggest they are fierce, specialized predators, but their prey and attack behavior are still unknown. The researchers say Trogloraptor is a close relative of goblin spiders (
Oonopidae), but it possesses a mosaic of ancient, widespread features and evolutionary novelties.
A team of citizen scientists from the Western Cave Conservancy and arachnologists from the California Academy of Sciences found these spiders living in caves in southwest Oregon. Colleagues from San Diego State University found more in old-growth redwood forests.
Charles Griswold, Curator of Arachnology, Joel Ledford, postdoctoral researcher, and Tracy Audisio, graduate student, all at the California Academy of Sciences, collected, analyzed, and described the new family. Audisio's participation was supported by the Harriet Exline Frizzell Memorial Fund and by the Summer Systematics Institute at the Academy, which is funded by the National Science Foundation.
A study of the new spider family was published
here in the open access journal
ZooKeys.
Photos: California Academy of Sciences 
