False Black Widow

Scientific Name: Steatoda grossa

Order & Family: Araneae: Theridiidae

Size: Females range from 6 to 10.5 mm in body length; males are smaller, roughly 4 to 6 mm.

False Black Widow

Natural Habitat

Often found in and around human dwellings, basements, crawl spaces, and dark corners of gardens or outbuildings.

Diet & Feeding

Feeds primarily on insects, including flies, crickets, and other spiders, using a tangled cobweb to capture prey.

Behavior Patterns

Primarily nocturnal and sedentary, they build messy, three-dimensional webs. They are reclusive and typically remain hidden in dark crevices durante the day.

Risks & Benefits

Benefits the ecosystem by controlling pest insect populations. While their bite can cause medically significant symptoms (Steatodism) similar to a black widow, they are not generally considered dangerous to healthy adults and are not aggressive.

Identified on: 5/16/2026