Cockroaches: Blattodea

Cockroaches are related closely to termites and mantids (such as the praying mantis) and are sometimes grouped with them. Adult cockroaches range in length from 0.8 to 3.1 inches (20.3 to 78.7 millimeters). They are flat and oval in shape, and they usually have four wings. Most species are uniformly dark in color and are typically black, brown, or reddish brown. Some species have unique markings, warning possible predators (PREH-duh-ters), or animals that hunt them for food, that they might be poisonous or taste bad. The larvae (LAR-vee), or cockroach young, look very similar to the adults. While many cockroaches have body chemicals that make them taste bad, most do not. Brightly colored species are mostly mimics, pretending to look like some other kind of insect that predators associate with a bad taste, painful bites, or stings. Some cockroaches that live in the tropics look like fireflies, ladybird beetles, or wasps. Almost nothing is known about the relationship of these cockroaches to the insects they mimic.

Cockroaches have strong, chewing mouthparts that point downward. The threadlike antennae (an-TEH-nee), feelers, are usually longer than the body. Their bodies are made up of many small segments too numerous to count easily. They have compound eyes, eyes with many lenses, but in some species, especially those that live in caves, they may be small or absent. The first part of the thorax is often shieldlike, and the edge often covers most of the head. The forewings, if there are any, are slightly thickened membranes with a network of supporting veins. These wings may be short, exposing part of the abdomen, or long, covering the abdomen entirely. The hind wings, if present, are sometimes fanlike, but they may also be very small. They, too, are somewhat like membranes and thinner, and they have a network of supporting veins. The cockroaches' long and spiny legs are especially suited for running, although some species rely on them for digging.