False Widow

Steatoda grossa

True spiderbeginnerVenom: Mild

About

A glossy dark cobweb-builder often found in cupboards, sheds, and basements — resembles a true widow but is only distantly related and far less venomous. Very hardy and low-maintenance: it favors cooler, darker microclimates (about 60-78°F), modest humidity, and can go months between meals as long as it has water. Give a small enclosure with anchor points for its tangled web, occasional misting, and crickets or flies every week or two. Shy and non-aggressive; its bite is minor, roughly a wasp sting, with no lasting effects. Solitary; very long-lived for a small spider (females up to ~6 years).

Taxonomy

FamilyTheridiidae

GenusSteatoda

Native regionCosmopolitan; often indoors in cool, dark spots

TypeCobweb (web)

Temperamentshy, non-aggressive; flees when disturbed; mild venom

Size & growth

Adult sizefemale 6-10.5 mm, male 4-10 mm

Length4.00–11.00 mm

Growth ratefast

Climate

Temperature60–78 °F

Humidity45–60%

Enclosure

Adult sizesmall enclosure (32oz+) with vertical web anchors

Substrateanchor points (sticks, cork, mesh) for a tangled cobweb; substrate optional

Substrate depth1-2 inches (web spider; rarely on the ground)

Water dishOptional

Feeding

Feeding modePredator (live prey)

Prey sizeflying insects, crickets

Adult cadence2-3 prey per week

Times kept: 1