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Spiders are often confused with insects,but they belong to a completely different group.
A spider has eight legs,but an insect has six. Its body has two parts while an insect has three. Also insects have antennae and most have wings, but spider do not have these. Spiders are some of the most feared and least understood in the animal world.
These hairy hunters are famous for spinning silk and giving a poisonous bite. There are about 37,000 known species and probably another 35,000 to be found. There is only about 30 species that are dangerous to people. Spiders live just about everywere, like forests, deserts, grasslands, caves ships and in our homes. Some spiders spin webs to catch ther prey while others leap out from hiding places or stalk their meals like a tiger.
Kinds of spiders
The order of spiders is divided into three suborders. In the first and most ancient spider group, mesothelae, there are only nine species. Unlike all other spiders, the mesothelae have 12 abdominal segments, two pairs of book lungs, and only two pairs of spinnerets. These spiders are very rare and found only in eastern Asia. The members of the second suborder, orthognatha, or mygalmorph spiders, include the tarantulas of north america. They are also primitive but are found all over the world, especially in tropical and subtropical habitats. These spiders move their jaws vertically, or up and down. All spiders use their jaws to soften or "chew" prey, but some mygalomorphs also use their jaws to dig burrows. The majority of spiders belong to the third group of spiders, labidognatha. Or araneomorph spiders, which includes the hunting spiders and the web spinners. These spiders are easily distinguished from the mygalomorphs because they move their jaws sideways, like a pair of pliers. The araneomorphs use their jaws to carry their egg sacs. "chew" large prey, transport small prey, or sing to their mates prior to mating
Tarantula
Belonging to the family theraphosidae, in the united states the name tarantula includes families such as the trapdoor and purseweb and the funnel-web spiders, in the tarantula suborder mygalomorphae. Tarantulas inhabit tropical to temperate regions in Africa, Asia, the middle east, south and central America, Mexico, and the southwestern united states.
They are seen in a variety of habitats, including desert scrublands, but most species live in rainforests. The tarantula family includes the largest spiders known.
The Goliath tarantula
(Theraphosa leblondi)
Inhabits south America, reaches a body length or 4 inches (10 centimetres) and a leg span of up to 10 inches (25 centimetres). Even the small tarantulas reach a relatively large body length of 1.5 inches (4 centimetres).
Colours
The majority of tarantulas are black or brown. Some species, however, exhibit striking colours. An example of this would be the mexican red-legged tarantula, with it's bright red leg markings.
Mexican Red Legged (Brachypelma smithi)
Burrows or other retreats
Some dig their own burrows, others use ready-made crevices or abandoned rodent hole. Some make their homes under rocks or logs or under the bark of trees. Others build silken retreats on trees, cliff faces, the walls of buildings, or in crop plants such as bananas and pineapples.
Tarantulas, like nearly all spiders, inject venom through their fangs. Despite their fearsome appearance and reputation, there are few if any substantiated reports of tarantula bite proving fatal to a human. The effects of tarantula venom are not well known, however,
While the bites of many new world species are generally reported to be no worse than a wasp sting, some south American species are reputed to be deadly or to cause severe pain, swelling, vomiting, cramps and shock. The tarantula is a nocturnal hunter.
It typically waits partially hidden at the entrance to its retreat to ambush passing prey. It has sensitive hairs that enable it to detect the size and location of potential victims from the vibrations caused by their movements.
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