The Sicariidae consist of a family of six-eyed spiders, of which the notorious, in North America occurring brown recluse spider (Loxosceles reclusa) is probably best known. This species and some other of this family, have a strong poison that may cause nasty wounds after a bite and in rare cases may even cause death. The spiders build an irregular, flat sheetweb to catch prey. A few species of the genus Loxosceles occur in Europe. The spiders of the other genus, Sicarius, occur elsewhere in the world.
The spiders of this genus formerly belonged to their own family, the Loxoscelidae, but were later assigned to the Sicariidae. They are nocturnal spiders which build their webs under stones. During the day, they hide themselves. They got their name Violin spiders due to the fact that there is a violin-shaped marking on their carapace.