Class Insecta
Insects (from Latin insectum, a calque of Greek ἔντομον [éntomon], “cut into sections”) are a class within the arthropods that have a chitinous exoskeleton, a three-part body (head, thorax, and abdomen), three pairs of jointed legs, compound eyes, and two antennae. They are among the most diverse group of animals on the planet and include more than a million described species and represent more than half of all known living organisms. The number of extant species is estimated at between six and ten million, and potentially represent over 90% of the differing metazoan life forms on Earth. Insects may be found in nearly all environments, although only a small number of species occur in the oceans, a habitat dominated by another arthropod group, the crustaceans.
- Anoplura – Sucking Lice
- Coleoptera – Beetles
- Dermaptera – Earwigs
- Dictyoptera – Mantids and Cockroaches
- Diptera – Flies
- Embiidina – Webspinners
- Ephemeroptera – Mayflies
- Hymenoptera – Ants, Bees, Wasps and Sawflies
- Hemiptera – True Bugs, Cicadas, Hoppers, Aphids and Allies
- Isoptera – Termites
- Lepidoptera – Butterflies and Moths
- Mallophaga – Chewing Lice
- Mecoptera – Scorpionflies, Hangingflies and Allies
- Megaloptera – Alderflies, Dobsonflies, and Fishflies
- Microcoryphia – Bristletails
- Neuroptera – Antlions, Lacewings and Allies
- Odonata – Dragonflies and Damselflies
- Orthoptera – Grasshoppers, Crickets, Katydids
- Phasmatodea – Walkingsticks
- Plecoptera – Stoneflies
- Psocoptera – Barklice and Booklice
- Raphidioptera – Snakeflies
- Siphonaptera – Fleas
- Strepsiptera – Twisted-winged Insects
- Thysanoptera – Thrips
- Trichoptera – Caddisflies
- Zoraptera – Zorapterans
- Zygentoma – Silverfish
