FAUNA : THE POISONOUS BLACK WIDOW SPIDER

Short Description about Black Widow Spider

Black widow spiders are easily recognizable. They’re plump, black, and shiny, with an hourglass-shaped, red mark on their abdomens. Sometimes, this red mark may take a slightly different shape. In other cases, the spider may have red markings on its back too.

This type of spider gets its name from its mating behavior. After mating, the females typically kill and then eat their male partners, leaving them as “widows.”

These spiders aren’t aggressive and only bite when they feel threatened. The bites usually aren’t fatal, but they can still cause some serious and uncomfortable symptoms.

If a black widow spider has bitten you, get medical treatment right away.

This spider type is found

throughout the world. While they are found all over the United States, they’re most common in the Southern and Western states.

Venom

This spider's bite is much feared because its venom is reported to be 15 times stronger than a rattlesnake's. In humans, bites produce muscle aches, nausea, and a paralysis of the diaphragm that can make breathing difficult; however, contrary to popular belief, most people who are bitten suffer no serious damage—let alone death. But bites can be fatal—usually to small children, the elderly, or the infirm. Fortunately, fatalities are fairly rare; the spiders are nonaggressive and bite only in self-defense, such as when someone accidentally sits on them.

The animals most at risk from the black widow's bite are insects—and male black widow spiders. Females sometimes kill and eat their counterparts after mating in a macabre behavior that gave the insect its name. Black widows are solitary year-round except during this violent mating ritual.

Webs and Feeding

These spiders spin large webs in which females suspend a cocoon with hundreds of eggs. Spiderlings disperse soon after they leave their eggs, but the web remains. Black widow spiders also use their webs to ensnare their prey, which consists of flies, mosquitoes, grasshoppers, beetles, and caterpillars. Black widows are comb-footed spiders, which means they have bristles on their hind legs that they use to cover their prey with silk once it has been trapped.

To feed, black widows puncture their insect prey with their fangs and administer digestive enzymes to the corpses. By using these enzymes, and their gnashing fangs, the spiders liquefy their prey's bodies and suck up the resulting fluid.

Source : National Geographic

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