April 01, 2001
Research Project: Class Insecta
Insects are invertebrates in the class Insecta from the phylum arthopoda. Arthropods include more than 850,000 species and form by far the largest phylum in the animal kingdom, exceeding in number all the other Phyla combined. The characteristic tough exoskeleton and jointed limbs are superimposed in a segmental body plan that reflects the evolution of arthropods from ancestors of the annelid worm. Insects, arachnids, myriapods and crustaceans are the major groups in this phylum (Nichols). Insects are the largest of this phylum and make up the largest class of all organisms and are recognized by taxonomist to have nearly one million recognized species. It is estimated that their are over ten million species still undiscovered. Because of this the insect orders are thought to be the least well known. Most of which are beetles and insects in tropical areas. Insects are part of 28 living orders which all have three body sections, head, thorax, abdomen and six legs and a pair of antenas. They are split in to two groups, Apterygota and Pterygota, Pterygota can fly while the more primitive Apterygota cannot (Gale Group).
Insects are all over the world, from the Tropics to the Tundras. They extremely diverse. While the order Grylloblattodea order of the Orthopteroid Orders thrives in cold icy places, the Mecoptera Order of the Hemipteroid Orders does best in the tropical areas of the world. Every Class is different and includes many kinds of insects. So here is the major 23 Orders. Order Microcoryphia, which include, Bristletails are part of the subclass Apterygota. Bristletails are jumping insects with long antennae, that are wingless, with very large eyes, a biting mouth, and three very fine tails. They live among stones or in woods and grass, and feed mostly on algae. Order Zygentoma is also part of the subclass Apterygota and include Silverfish, and fibrebrats. Silverfish are wingless, with small eyes, a chewing mouth, they have a long antennae, and three thin tails. Their flat bodies are covered in silvery scales. Silverfish like to live in warm damp places, such as under sinks, in bathrooms, and in bookshelves. Order Ephemeroptera are part of the Pytergota subclass and include Mayflies, Shadflies Adult Mayflies and Shadflies have wings, chewing mouthparts (which they don't use, because they die before they feed as adults -- usually within one day), small antennae, and two or three long tails. Larvae can live as long as four years. Order Odonata is part of the large subclass Pterygota and include Dragonflies As you should know they have long thin bodies, two pairs of long narrow wings, and very large eyes. Dragonflies are the best fliers of all insects. They are also predators, feeding on other insects which they catch during flight. The larvae live in water, and are also hunters. Order Dictyoptera is part of the advanced Pterygota subclass and include the very successful cockroach. Cockroaches (Sub-order Blattodea) have flattened oval bodies with wings (but they seldom fly -- they have well developed legs and scurry about), very long antennae that lie back along the side of the body, large eyes and chewing mouthparts. They are the most successful order due to their adaptive skills. Order Isoptera is part of the unprimative Pterygota subclass and include Termites. We all know that Termites are destructive to wood and major pest. They are social insects, living in colonies and have soft bodies, biting mouthparts, small eyes and short antennae. Order Orthoptera which are part of the also common Pterygota Subclass include grasshoppers, locusts, katydids, crickets. Orthoptera insects have long, strong legs which they use for jumping and two sets of wings. The front set of wings is hardened and used for protection as well as for flying. Males also use their legs and the rough parts of their wings to make the characteristic cricket...
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