The 7 families and 2,750 species in the order Isoptera are never found more than 50 degrees north or south of the Equator. A typical termite is pale, soft, and wingless, with chewing or biting mandibles and short antennae, but the different castes within a colony have varying features. The reproductives, including kings and queens, have two pairs of long wings, short cerci, and round or oval heads. The sterile soldiers have proportionately larger heads than the workers. Eyes are often reduced or absent. Termites live in mud nests or vast underground mazes with huge ventilation chimneys above the ground. Most eat dead or rotting wood--this is the only order in which all families digest cellulose--and many attack crops or wooden buildings.
 

The pronotum of all castes is rounded at the back and may, in some species, appear almost heart-shaped. Soldiers have no eyes. Coloration is cream or light to dark brown.
 

Eggs are laid in the colonies, which are found either in soil or in damp wood that touches the ground.
 

Worldwide, in warm regions. In various habitats, in soil and wood.
 

Some species are timber pests. One North American species is such a serious pest that there are special building regulations to help prevent the damage it can cause.