Southern House Spider
Adult male southern house spiders are leggy and fast unlike their younger selves or the females that stay put in their silken lairs. Males give up feeding almost entirely and instead devote all their energy to prowling the building for receptive females. Males have long and prominent pedipalps at the head.
Filistatidae -- Crevice Weaver Spider Family
As the family name suggests these spiders inhabit crevices in buildings or cliff faces and construct silk webbing extending on the surface around their hiding spot. The females are essentially black in color where as males are lighter brown. Once mature the males abandon their webs and roam about in search of females. Their appearance suggests something dangerous like a recluse spider, but in fact these spiders are essentially harmless to humans. They are very common, especially around older buildings in both Phoenix and Tucson areas. Originally an old world species, the Southern House Spider has been distributed to warm climates the World over. But Arizona also has a native crevice spider, Kukulcania arizonica which tends to be a bit large and inhabit rural and natural areas. Otherwise the two species are inseparable to the eye.
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Michael J. Plagens, page created 11 Aug. 2008,
updated 30 Oct. 2019.