Article in English: Black widow spiders are found across the U.S and Canada, and in other temperate regions around the world. They are the most venomous spiders in North America. The female is the easiest to recognize -- and the most dangerous. She is coal-black, with a spherical abdomen and a red hourglass-shaped mark on her belly. Her body is approximately half an inch long, but she has a total length of 1.5 inches (3.8 cm) with her legs extended.  The male is about half the size of the female and is brown or grey. He usually has several red dots on his abdomen and may have a yellow or red band across his back. Male black widow spiders are not venomous. Young black widows, known as spiderlings, are white or yellow-white when they first hatch. They become darker as they grow. They may have yellow or red patches across their backs, resembling the adult male. It is impossible to tell male and female spiderlings apart. At this stage, both are harmless to humans. The black widow spider is timid and reclusive, preferring to make its home in dark, protected areas, such as in boxes, among firewood and under ledges. It is nocturnal, actively hunting at night.  The black widow spider's web is usually located within a foot of the ground. It is slightly erratic in appearance and made with stronger silk than most other spider webs. The web is used to catch prey and to hang the female's cocoon of eggs. Black widows are usually found in dark corners of the house or around the edges of a yard or garage where their webs will have a lesser chance of being disturbed. They may also be found under vehicles, even those that are being driven periodically. Check for webs near the tires, or under/around the engine. Black Widows are territorial, so their webs are often spaced about a foot apart. Female Black Widow spiders have very powerful venom -- in fact, it is said to be15 times stronger than that of a rattlesnake. The venom is a neurotoxin. Symptoms include muscle aches, abdominal pain, breathing difficulties and nausea. The majority of Black...

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