The prevalence of sexual cannibalism in Latrodectus by a female spider has inspired the common name “black widow spider”. The female Latrodectus most of the time eat their male Latrodectus partners after mating. The clue to this fact is due to the potency of venom in female species, which is at least three times more potent than that of the males.
The black widow spider is a cobweb builder whose silk is very strong. The female constructs a web of crisscrossed silk threads with no recognizable pattern and with a dense area of silk, usually to one side, that serves as the spider’s daytime retreat. At night, the female hangs belly upward in the center of the web. She does not leave her hidden web voluntarily.
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