Spiders are the largest group of arachnids. There are more then 34,000 named species worldwide, including 3,000 species in North America. Spiders can easily be identified by their 4 pairs of legs. Each leg is segmented into many different sections or joints. Most Spiders have 8 pairs of eyes. A few have less then 8 and some species have none at all. The eyes of a spider are usually arranged in 2 or 3 rows. Spiders usually have 6 silk glands called spinnerets located beneath the abdomen. Not all spiders spin webs, some live in burrows which they line with silk. Spiders are not considered insects. They are from the order of Araneae. (Arachnids) Insects have only 6 legs, whereas spiders have two more for a total of 8 altogether. All spiders are predators. They feed mostly on insects, but some of the larger species prey on small animals! There is a common mistake most people make about the 'Daddy Long Legs'. This is not actually a spider at all, it is classified in the order or 'Opiliones'. Tarantulas (Family Theraphosidae) Certain South America species are deadly poisonous, but the bite of a North American Tarantula is as dangerous as a bee sting. There are some male spiders that release long silken strands, which they use like parachutes to float in the wind to another location. Black Widow Spider (Latrodectus mactans) Of all spiders, the Black Widow is the most feared. The female's venom is especially poisonous to people. The Fishing Spider (Dolomedes tenerosus) If disturbed this spider can go below the water and remain motionless for 30 minutes. Air trapped by his body allow him to breathe. Like all arachnids, spiders have an abdomen and a cephalothorax. These are separated by a waist or pedicel. The thorax is protected by a covering called a carapace. Most spiders lay eggs in silken sacs. Some place the egg sac in their webs, while others attach it to twigs and leaves. A few spiders carry the sac with them at all times. Spiders should be considered very beneficial to us because they help keep the enormous insect population like mosquitoes in check. The correct term for a newly hatched spider is a spiderling. The young, though smaller, resemble their adults from the moment they emerge from their egg sac. Contrary to what most people think, only a few spiders actually bite people, and the venom of most of these is quite harmless. Tarantulas (Family Theraphosidae) Male Tarantulas are short-lived, yet females have been known to live for as many as 30 years ! Trapdoor Spider (Family Ctenizidae) These spiders nest in tubelike burrows they dig into the ground. They seal the nest with a hinged lid similar to a folding trapdoor. Spitting Spiders (Family Scytodidae) There are many types of Spitting Spiders. They have spitting glands within the thorax which make a sticky substance to catch prey. American House Spider (Achae. tepidariorum) These spiders spin irregular webs made of sticky strands. When these webs catch dust and dirt they become 'Cobwebs'. Black Widow Spider (Latrodectus mactans) Male Black Widow Spiders do not bite. After they mate, the female often eats the male spider earning her the name 'Widow'. Hammock Spider (Pityohyphantes costatus) These spiders get their name from the hammock like sheet web they construct between fence posts and tree branches. Orb Weaver Spiders (Araneaus spp.) Like most spiders who spin webs, they construct a new web each night. They spin the web in complete darkness by touch alone! Barn Spiders (Araneus cavaticus) These spiders stay in their webs at night to wait for prey. In the daytime, they move above it and are attached by a silk line. The Shamrock Spider (Araneus trifolium) This spider waits at the side of his web between grass stems. They make a tent to hide it by tying leaves together with silk. The Shamrock Spider (Araneus trifolium) Their webs are made each night in the grass. They can be clearly seen with the dew at sunrise. At night they eat the old one. Bola Spider (Mastophora bisaccata) This spider catches prey by producing a silken line which has drop on the end that that resembles the South American Bola. Wolf Spiders (Family Lycosidae) This spider lives in burrows and seldom emerges from them. They lie in wait for prey ready to pounce on a passing insect. Burrowing Wolf Spiders (Geolycosa spp.) These spiders construct vertical burrows in sand several feet deep. They cement the sand with silk to make the walls sturdy. Ant-mimic Spiders (Castianeira spp.) These spiders usually live near anthills. Their look and antlike behavior helps them to confuse predators. Goldenrod Spider (Misumena vatia) This spider 'Flower Spider' changes its to yellow which allows it to camouflage itself on Goldenrod and daisies. Jumping Spiders (Family Salticidae) There are many different types of Jumping Spiders. They get their name from the spectacular leaps catching their prey. Jumping Spiders (Family Salticidae) These spiders have the sharpest vision of all spiders. When they leap onto their prey, their spinnerets create a silken dragline. Many spiders who spin webs do not wait in them for prey. They attach themselves to the web by a silk line which senses the vibrations of a struggling insect. Species of spiders that spin webs each have a distinctive pattern. Some are shaped like funnels, some are round, and others are zigzagged.