Blattodea is an order of insects that contains cockroaches and termites. Formerly, termites were considered a separate order, Isoptera, but genetic and molecular evidence suggests they evolved from within the cockroach lineage, cladistically making them cockroaches as well. The Blattodea and the mantis are now all considered part of the superorder Dictyoptera. Blattodea includes approximately 4,400 species of cockroach in almost 500 genera, and about 3,000 species of termite in around 300 genera.
Blattodea
American cockroach
Termites
Cathedral termite mounds, Northern Territory, Australia
Insects are hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body, three pairs of jointed legs, compound eyes, and a pair of antennae. Insects are the most diverse group of animals, with more than a million described species; they represent more than half of all animal species.
Insect
Insect: Six legs, three-part body (head, thorax, abdomen), up to two pairs of wings
Spider: eight legs, two-part body
Woodlouse: seven pairs of legs, seven body segments (plus head and tail)