The family Hypochilidae (lampshade weavers) includes just a dozen described species, including two species known from China in the genus Ectatosticta and 10 species in the United States in the genus Hypochilus (Platnick 2013). The body of a hypochilid is dorsoventrally (i.e., top to bottom) flattened and the legs are long, especially in males. Member of this family are the only araneomorph spiders in North America with two pairs of book lungs. (Paquin and Hedin 2005) Hypochilus species are found in three disjunct regions of North America: the southern Appalachian Mountains (five species), the southern Rocky Mountains (two species) and the California mountains (three species) (Catley 1994; Hedin 2001; Paquin and Hedin 2005).
Hypochilus are typically found on the bare surfaces of boulders, on walls of overhanging cliffs (often near streams and creeks), on the walls of cave entrances, and sometimes in man-made habitats such as mines and culverts. The broad circular web (Gertsch 1958, 1964), sometimes said to resemble a lampshade, is constructed of a heavy mesh of sticky, hackle-band threads (i.e., silk produced from the cribellum and calamistrum) and attached to a substrate by numerous dry lines. The spider rests against the rock face at the center of the web with its long, thin legs held spread apart in a distinctive posture, often bent at a right angle between the femur and patella. (Bradley 2013) Hypochilus spiders can run quickly for a short distance if disturbed (Paquin and Hedin 2005).
Shear (1969) investigated the predatory behavior of H. gertschi. Fergusson (1972) studied the natural history of H. pococki(as H. thorelli). Foelix and Jung (1978) reported on aspects of the anatomy of H. thorelli. Riechert and Cady (1983) and Hodge and Marshall (1996) studied the community ecology of H. thorelli and ecologically similar spiders with which it coexists. Coyle (1985) studied the life cycle of H. pococki. The male reproductive system was studied by Alberti and Coyle (1991). The mating systems and reproductive biology of H. pococki were studied by Eberhard et al. (1993) and Catley (1993), respectively.
As noted above, ten Hypochilus species were recognized as of 2013. Hypochilus thorelli was described by Marx in 1888 and W.J. Gertsch described two additional species in 1958 (H. petrunkevitchi) and 1964 (H. bonneti). Gertsch, in turn, had a new Hypochilus species named after him by Hoffman in 1963 (H. gertschi). Platnick (in Forster 1987) described four new species of Hypochilus (H. pococki, H. coylei, H. sheari, and H. kastoni) and Catley (1994) described two additional species (H. jemez from New Mexico and H. bernardino, previously misidentified as H. petrunkevitchi, from southern California).Catley also included a map showing the known distributions of all ten known Hypochilus species.The systematics of H. coylei and H. sheari was examined by Huff and Coyle 1992. Hedin (2001) and Hedin and Wood (2002) investigated the phylogenetics and phylogeographic structure of Hypochilus. The two Ectatosticta species were described in 1889 (E. davidi) and 2009 (E. deltshevi).
Paquin and Hedin (2005) briefly reviewed the taxonomic history of Hypochilidae, noting its significance as the apparent sister group to all other araneomorph spiders (Paquin and Hedin 2005 and references therein).
Catley (1994) suggested that many Hypochilus species known from only a few populations may be vulnerable to extinction.