Steatoda

Steatoda is a genus of spiders in the family Theridiidae. Commonly called false widows or cupboard spiders, Steatoda comprises over 100 described species with a cosmopolitan distribution, occurring in temperate and tropical regions. The genus name is derived from Greek steatos, meaning "fat," alluding to the rounded abdomen typical of many species.

Members are typically small to medium-sized spiders with a globular abdomen and legs arranged sideways (laterigrade). Coloration is variable, but brown to dark forms with pale markings are common. They construct irregular, tangled webs in sheltered places such as corners of buildings, under furniture, and in sheds. They are largely nocturnal and rely on their webs to capture prey.

Several species have become familiar in human habitats. Steatoda nobilis, the noble false widow, has expanded its range in Europe and parts of North America. Steatoda grossa and Steatoda triangulosa are also commonly encountered in homes in various regions. In natural settings, Steatoda spiders inhabit woodlands, caves, and grasslands, often near animal nests.

Bites to humans are uncommon. When they occur, symptoms are usually mild and localized, such as pain and swelling; severe systemic reactions are rare and not characteristic of the genus as a whole. Steatoda spiders are sometimes mistaken for true widows (Latrodectus) because of superficial resemblance, but their venom is typically less potent.