Each season, female brown widow spiders lay several egg sacs, each with 120 to 150 eggs. The egg sacs are distinctive, with silky spikes projecting from the surface, much like a thistle.

When female brown widow spiders bite, they typically inject less venom than a black widow spider, and the bites usually don’t cause any symptoms beyond the discomfort of the wound.

A female brown widow tends to her web. Male spiders may stumble onto the webs of immature females while looking for adults. Photogrpah by MCB Andrade. If that’s the case, ...

Published Apr 30, 2018 at 1:07 PM EDT Updated Apr 30, 2018 at 1:07 PM EDT Updated ...

Young female brown widows were 9.5 per cent larger than southern black widows and mature females could produce multiple egg sacs at a time, whereas southern black widows produce just one. Journal ...

Male brown widow spiders seek to mate with older, ... Nov. 8, 2022 — When it comes to spider love, female widow spiders hold the key to attracting mates, ...

They also compared rates of growth and fertility between brown and black widows, finding that sub-adult brown widow females were 9.5 percent larger than black widows, and adult female brown widows ...

Brown widow spider. These spiders also are found in the Southern and Western U.S. ... Adult female brown widows are brown and often have an orange hourglass shape on their abdomen.

Of the over 46,000 known spider species, only about 200 have venom potent enough to be of medical concern. This is assuming, of course, that an individual isn’t allergic to specific components ...

Scientists in Israel have observed a strange behavior among brown widow spiders: When given the choice, the males of this species prefer to have sex with older females even though they’re less ...