The Common House Spider, Achaearana Tepidariorum (C. L. Koch)

The common house spider, Achaearanea tepidariorum (C. L. Koch), may be the most abundant of the several species of spiders that live in the company of man in the southeastern United States, especially in Florida. Although Archer (1947) thought that A. tepidariorum was less common inside houses than Pholcus phalangioides Fuesslin (Pholcidae) in Alabama, he also noted its abundance.

Levi (1967) considered A. tepidariorum to be a cosmopolitan species. Although the species was first described from Germany, it appears to be native to South America, judging from the numerous similar relatives which occur there. It is abundant in Central America and Mexico, and occurs as far north as southern Canada (Levi, 1955). It has been recorded from most of the contiguous United States (Levi and Randolph, 1975). The species probably now has a worldwide distribution, having been carried around the world by man on plants. Although A. tepidariorum belongs to the same family (Theridiidae) as the notorious black widow spiders (Latrodectus spp.), it is not known to be dangerous to humans. One case of serious allergic reaction to the bite of A. tepidariorum is known from Gainesville, Florida.