(subphylum Atelocerata, class Insecta)
Subclass and order of minute (0.6–2 mm long), primitive, apterous, white insects, which lack eyes and antennae and have reduced, entognathous, piercing mouth-parts. Proturans are elongate, with segmented legs, the anterior pair used for sensory purposes, the middle and posterior pair for walking. The abdomen carries a pair of short styli (rudimentary limbs) on the basal three segments and the pseudocelli found on the head may represent antennal bases or postantennal organs. Species in this rare group live under bark, stones, or among rotting vegetation, and are sometimes subterranean in habit. Proturans exhibit anamorphosis, one extra segment being added at each moult. Metamorphosis is simple. There are 118 species, world-wide in distribution.
Subjects: Zoology and Animal Sciences.