Bug Identifier
False Black Widow (Cupboard Spider)
Community identification

False Black Widow (Cupboard Spider)

Steatoda grossa

Order & Family
Order: Araneae; Family: Theridiidae
Size
Females: 6–10.5 mm (body length); Males: 4–6 mm. Leg span can reach up to 25 mm.
See this bug in the Encyclopedia

Natural Habitat

Commonly found indoors in dark, secluded areas such as cupboards, basements, and behind furniture, as well as outdoors in gardens and garage corners.

Diet & Feeding

Carnivorous; feeds primarily on other arthropods including woodlice, crickets, flies, and occasionally other spiders.

Behavior Patterns

They build messy, three-dimensional cobwebs. They are nocturnal and shy, usually retreating if disturbed. This specific specimen appears to be male, indicated by the enlarged pedipalps (the boxing-glove-like structures near the head).

Risks & Benefits

Benefits the ecosystem by controlling household pests. While they can bite if squeezed or threatened, they are not aggressive. Bites may cause localized pain and minor blistering but are generally not medically significant for healthy adults, unlike the true Black Widow.