The recluse spiders, also known as brown spiders, fiddle-backs, violin spiders, and reapers, is a genus of spiders that was first described by R. T. Lowe in 1832. They are venomous spiders known for their bite, which sometimes produces a characteristic set of symptoms known as loxoscelism.
Ground spiders comprise Gnaphosidae, the seventh largest spider family with over 2,000 described species in over 100 genera distributed worldwide. There are 105 species known to central Europe, and common genera include Gnaphosa, Drassodes, Micaria, Cesonia, Zelotes and many others. They are closely related to Clubionidae. At present, no ground spiders are known to be seriously venomous to humans.
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.
Drymusa is a genus of false violin spiders that was first described by Eugène Simon in 1892. They physically resemble violin spiders (Loxosceles), but their bites are not believed to be medically significant. Originally placed with the spitting spiders, it was moved to the Loxoscelidae in 1981, then to the Drymusidae in 1986.
Prodidomidae is a family of spider, sometimes called long-spinneret ground spiders. It was formerly regarded as a subfamily of Gnaphosidae, but was raised to a family in 2022.
Ariadna is a genus of tube-dwelling spider.
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.
Scytodes univittata is a species of spitting spider in the family Scytodidae. It is generally found in Turkmenistan, Kyrgyzstan and India. This species has been introduced to Hawaii, Mexico, Cuba, Venezuela, Brazil, Paraguay, Chile, Canary Islands, Spain, Italy, Cyprus, Egypt and there is a subspecies Scytodes u. unilineata endemic to Myanmar.
