Corinnidae is a family of araneomorph spiders, sometimes called corinnid sac spiders. The family, like other "clubionoid" families, has a confusing taxonomic history. Once it was a part of the large catch-all taxon Clubionidae, now very much smaller. The original members of the family are apparently similar only in that they have eight eyes arranged in two rows, conical anterior spinnerets that touch and are generally wandering predators that build silken retreats, or sacs, usually on plant terminals, between leaves, under bark or under rocks.
Castianeira is a genus of ant-like corinnid sac spiders first described by Eugen von Keyserling in 1879. They are found in Eurasia, Africa, and the Americas, but are absent from Australia. Twenty-six species are native to North America, and at least twice as many are native to Mexico and Central America.
Lycosa is a genus of wolf spiders distributed throughout most of the world. Sometimes called the "true tarantula", though not closely related to the spiders most commonly called tarantulas today, Lycosa spp. can be distinguished from common wolf spiders by their relatively large size. This genus includes the European Lycosa tarantula, which was once associated with tarantism, a dubious affliction whose symptoms included shaking, cold sweats, and a high fever, asserted to be curable only by the traditional tarantella dance. No scientific substantiation of that myth is known; the venom of Lycosa spiders is generally not harmful.
Micrathena, known as spiny orbweavers, is a genus of orb-weaver spiders first described by Carl Jakob Sundevall in 1833. Micrathena contains more than a hundred species, most of them Neotropical woodland-dwelling species. The name is derived from the Greek "micro", meaning "small", and the goddess Athena.
Hogna is a genus of wolf spiders with more than 200 described species. It is found on all continents except Antarctica.
Ctenus is a genus of wandering spiders first described by Charles Athanase Walckenaer in 1805. It is widely distributed, from South America through Africa to East Asia. Little is known about the toxic potential of the genus Ctenus; however, Ctenus medius has been shown to share some toxic properties with Phoneutria nigriventer, such as proteolytic, hyaluronidase and phospholipase activities, in addition to producing hyperalgesia and edema. The venom of C. medius also interferes with the complement system in concentrations in which the venom of P. nigriventer is inactive, indicating that some species in the genus may have a medically significant venom. The venom of C. medius interferes with the complement component 3 (C3) of the complement system; it affects the central factor of the cascades of the complement, and interferes with the lytic activity of this system, which causes stronger activation and consumption of the complement components. Unlike C. medius, the venom of P. nigriventer does not interfere with lytic activity.
Eustala is a genus of orb-weaver spiders first described by Eugène Simon in 1895.
Alpaida is a genus of South American orb-weaver spiders first described by Octavius Pickard-Cambridge in 1889.
