SpidersMy essay is on spiders. I have chosen a few spiders to report about.Ialso have some basic info about spiders in general.Spiders comprise a large,widespread group of carnivorous arthropods. They have eight legs, can producesilk, and usually have poison glands associated with fangs.
More than 30,000species of spiders are found on every continent except Antarctica in almostevery kind of terrestrial habitat and a few aquatic ones as well. Spiders rangein body size from about 0.5 mm (0.
02 in) to 9 cm (3.5 in). The term spider isderived from the Old English spinnan ( “to spin” ) referring to the group’s useof silk. Spiders make up the order Araneae in the class Arachnida, which takesits name from the mythological character Arachne, a peasant girl who challengedthe weaving skill of the goddess Athena.
Arachne equaled Athena’s skill in acontest, and in response to Athena’s anger she hanged herself. In belatedremorse Athena changed the body of Arachne into a spider and allowed her toretain her weaving skill.My first selection is the brown recluse spider. The brown recluse spider(Loxosceles reclusa) is a poisonous spider in in the United States. Its mostlyfound from Kansas and Missouri, south to Texas, and west to California. Foundin sheltered places indoors and outdoors it is about 10 mm (.4 in.
) long andhas an orange-yellow body with a dark violin-shaped design on its back. Itsbite isn’t usually fatal to humans, the venom destroys the skin and it may takea few months to heal. The brown recluse is mostly active at night. it feeds onsmall insects that it paralyzes with its poison.
The Black WidowThe black widow, Latrodectus mactans, is a poisonous spider of thefamily Theridiidae, order Araneida. The female, about 1.3 cm (0.5 in) long, isglossy black, densely clothed with microscopic hairs, and has a red hourglassmark on the underside of the abdomen.The male, which is rarely seen, is smaller than the female and has fourpairs of red marks along the sides of the abdomen. The black widow is foundworldwide in the warmer regions in every state in the United States exceptAlaska and Hawaii; it lives in a variety of natural and domestic habitats.
Generally, the females are not aggressive unless agitated, although they areprone to bite when guarding an egg sac. The venomous bite of the black widowspider, Latrodectus mactans, causes muscle spasms and breathing difficulty inhumans and may be fatal. The female is distinguished by a red hourglass markingon its underside. The black widow eats a diet of insects, spiders and centipedescaptured in its web.
After mating, the female may ensnare and feed upon hermate–hence the name black widow. Its venomous bite causes muscle spasms anddifficulty in breathing.TarantulasIn common American usage, tarantulas are the large, hairy long-livedspiders that make up the family Theraphosidae. Related forms such as funnel-webspiders and trap door spiders are also often called tarantulas. The name camefrom a smaller wolf spider of Europe but was then applied by explorers of theNew World to the giant spiders that they encountered. No North American specieshas a venom that is dangerous to humans, but tarantula body hairs may induce anallergic reaction.
Tarantulas can give you a painful bite. Tarantulas occur inwarmer regions, where they feed on both invertebrates and small vertebrates.Many grow to about 2.5 to 7.5 cm (1 to 3 in) long, with a 13-cm species (5-in)legspan, and some South American bird-catching species are larger.
Sometarantulas reach an age of 20 years.