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Home » Guide » Arthropods (Arthropoda) » Chelicerates (Chelicerata) » Arachnids (Arachnida) » Spiders (Araneae) » True Spiders (Araneomorphae) » Entelegynae » Cobweb Spiders (Theridiidae) » Steatoda » False Black Widow (Steatoda grossa)

Species Steatoda grossa - False Black Widow

Classification · Synonyms and other taxonomic changes · Identification · Range · Habitat · Season · Food · Life Cycle · Remarks · Print References · Internet References

Spiders in rural Western WA (1 of 2) - Steatoda grossa

Spider was in my bed, not familiar with - Steatoda grossa

Max's Shower Spider - Steatoda grossa - male

Small Spider Found in Apartment - Steatoda grossa

false black widow - Steatoda grossa - female

Classification

Kingdom Animalia (Animals)

Phylum Arthropoda (Arthropods)

Subphylum Chelicerata (Chelicerates)

Class Arachnida (Arachnids)

Order Araneae (Spiders)

Infraorder Araneomorphae (True Spiders)

No Taxon (Entelegynae)

Family Theridiidae (Cobweb Spiders)

Genus Steatoda

Species grossa (False Black Widow)

Synonyms and other taxonomic changes

Teutana grossa

Identification

Some diagnostic drawings:

General habitus

Male palp:

Female epigyne:

Eye arrangement (male):

Range

Imported from Europe; In North America it has now been found in states along the east and west coasts as well as those bordering the Great Lakes. Specimens have also been collected in Colorado. It's also considered a cosmopolitan species and is found in other countries all over the world.

Habitat

In and around homes and buildings.

Season

Males mature in summer and autumn; adult females can be found year-round.

Food

Any arthropods that are snagged in the cobweb. This species is a specialist on pill bugs and real black widow spiders.

Life Cycle

Female Life Cycle:

Remarks

The bite of this spider might produce symptoms that are similar but much less severe than those of a black widow bite. In some cases blistering may form at the site of the bite along with physical discomfort that lasts for several days.

Print References

Branch, 1943. On the life history and progressive factor in growth of Teutana grossa Koch. Bulletin Southern California Academy of Sciences, 42: 34-38.

Internet References

Auburn.edu - range.

Colorado Spider Survey database

www.ipm.ucdavis.edu - How to Manage Pests of Homes, Structures, People, and Pets by R. S. Vetter

Contributed by john and jane balaban on 10 September, 2004 - 5:30pm
Additional contributions by Lynette Elliott, Jay Barnes, Christopher C Wirth, kschnei, jsloan, Mandy Howe
Last updated 7 March, 2015 - 9:56am

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