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False black widow (male)

Steatoda grossa

Description:

Like black widows, the female S. grossa is 6-10.5 mm in length and dark colored with a round, bulbous abdomen. Typical coloration ranges from purplish brown to black, with light-colored markings. Unlike black widows, redbacks, and other Latrodectus species, S. grossa does not have a bright red hourglass pattern or any other bright markings. Like many spiders, the male is sometimes smaller but can many times be nearly as long as the females. It measures 4.1-10.0 mm in length and is thinner than the female. The two sexes are colored similarly; however, the sexually mature male almost always has lighter, more reddish-coloured legs than the female. S. grossa spiders may shed up to six times (instars) before reaching maturity. They can go several months without feeding, provided they have access to water. A well-fed female can lay three or more egg sacs each year. Each egg sac typically contains between 40-100 eggs. The mother can often be observed watching her eggs for hours, even days, at a time once the eggs start changing color and grow close to hatching. At normal household temp/humidity, an egg will usually hatch within a month of being laid. The spiderlings are independent from time of hatch. Female S. grossa spiders can live up to six years; the typical lifespan for the male is 1-1.5 years. Males often die shortly after mating.-Wikipedia

Habitat:

Found under a half sheet of plywood.

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Brian38
Spotted by
Brian38

Federal Way, Washington, USA

Spotted on Mar 27, 2017
Submitted on Mar 27, 2017

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