Six-eyed sand spider

Description

Hexophthalma hahni (synonyms Sicarius hahni and Sicarius testaceus), known along with other members of the genus as the six-eyed sand spider, is a member of the family Sicariidae, found in deserts and other sandy places in southern Africa. Due to their flattened stance and laterigrade legs, they are also sometimes known as six-eyed crab spiders. Its specific name honours Carl Wilhelm Hahn. All species of Hexophthalma produce venom that can have necrotic (dermonecrotic) effects, capable of causing serious or even life-threatening wounds, particularly if the wound becomes infected or the venom spreads in the body. The necrotic effects are caused by a family of proteins related to sphingomyelinase D, present in the venom of all sicariid spiders. Most Hexophthalma species, though, including H. hahnii, have only been studied in vitro, and the detailed effects of their venom in humans and other vertebrates are unknown. No records of bites in southern Africa have been proven. Hexophthalma is a genus of spiders in the family Sicariidae. Although the genus was originally erected in 1878 (then with the name Hexomma), it was merged into the genus Sicarius in the 1890s, and remained unused until revived in 2017, when it was discovered that the African species then placed in Sicarius were distinct. The English name six-eyed sand spiders is used for members of the genus, particularly Hexophthalma hahni. Species in the genus have necrotic (dermonecrotic) venom, and can potentially cause serious or even life-threatening wounds. The genus was first created in 1878 by Friedrich Karsch as Hexomma, with the sole species Hexomma hahni. By 1879, though, Karsch had realized that this name had already been used in 1877 for a species of harvestman, so he published the replacement name Hexophthalma. In 1893, Eugène Simon transferred Hexophthalma hahni to the genus Sicarius, and Hexophthalma fell out of use, until a phylogenetic study in 2017 showed that the African species of Sicarius, including Sicarius hahni, were distinct, and revived the genus Hexophthalma for them. Species of Hexophthalma produce venom that can have necrotic (dermonecrotic) effects, capable of causing serious or even life-threatening wounds, particularly if the wound becomes infected or the venom spreads in the body. The necrotic effects are caused by a family of proteins related to sphingomyelinase D, present in the venom of all sicariid spiders.