Sicarius (spider)


Sicarius is a genus of recluse spiders that is potentially medically significant to humans. It is one of three genera in its family, all venomous spiders known for a bite that can induce loxoscelism. They live in deserts and arid regions of the Southern Hemisphere, and females use a mixture of sand and silk when producing egg sacs. Most are native to South America, with the exception of Central America's S. rugosus, known primarily for its self-burying behavior.

Description

Sicarius spiders can grow up to long, and have six eyes arranged into three groups of two. Physically, they resemble crab spiders and members of Homalonychus, but they lack the characteristic violin-shaped marking of the more well-known members of its family, Sicariidae the recluse spiders.
They can live for a very long time without food or water. Some can live for up to fifteen years, making them among the longest-lived spiders, behind the trap-door spiders and tarantulas, many known to live for twenty to thirty years. The oldest recorded spider is Number 16, a trap-door spider that died to a parasitic wasp at forty-three years old.

Venom components and effects

Like all recluse spiders, these produce a dermonecrotic venom that contains sphingomyelinase D, an enzyme in the sphingomyelin phosphodiesterase family. It is somewhat unique to them, otherwise only found in a few pathogenic bacteria. The venom causes bleeding and damage to many organs of the body, though only S. ornatus and a few others have been proven to be extremely toxic on the order of Hexophtalma hahni or several other African sand spiders.

Taxonomy

This genus was erected by Charles Athanase Walckenaer in 1847 with the single species, S. thomisoides. In 2017, the number of species decreased after a phylogenetic study showed that the South African species formerly included here were actually distinct, instead belonging to the genus Hexophthalma.
It is one of only three genera in its family, and is placed in the same subfamily as Hexophthalma:

Species

it contains twenty-one species, found in South America, Costa Rica, El Salvador, and Nicaragua:
In synonymy:
Transferred to Hexophthalma