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Zorapteran
Zorapteran, common name for minute, rarely seen insects that live in organic debris and sawdust. These obscure creatures are sometimes called angel insects; Zorapterans occur in small to relatively large colonies under bark, in moist leaf litter or rotting logs, and under wood pieces buried in piles of old sawdust. They are collected for study by carefully sifting and inspecting such debris. About two dozen species occur in forested regions throughout the world, except in Australia. At least three species occur in North America, mostly in wetter regions of the Southeastern United States and Hawaii.
Zorapterans have chewing mouthparts and feed on fungi and small, dead arthropods. They have slender legs and an oval, soft body, 3 mm (0.13 in) long or less. Zorapterans have relatively long, nine-segmented antennae and a pair of short tail filaments, or cerci, at the end of the abdomen. When this group was first named, only wingless forms were known, and the wingless condition was thought to be a distinctive characteristic of this group. It was subsequently discovered that mature adults of both sexes may be either winged or wingless. Wingless forms lack both compound and simple eyes (ocelli) and commonly have a pale-colored body. Winged zorapterans generally have three compound eyes, three ocelli, or simple eyes and a dark-colored body. When present, both pairs of wings are membranous with few veins, and the front pair are distinctly larger than the rear. Winged adults are similar to ants and termites in that they shed their wings after mating and dispersal.
Zorapteran eggs are tiny, pale, and ovoid. Nymphs have simple metamorphosis and resemble small, wingless adults as they develop through four growth stages, or instars.
Zorapterans are rare and secretive, so relatively little is known of their habits. Their behavior somewhat resembles that of termites, and they may have a primitive social structure. Some species have an elaborate premating ritual: Males secrete a liquid substance from a gland in their head and present this material to the female. Females allow mating only after receiving this courtship gift and evaluating its quality.
Scientific classification: All known zorapterans belong to the genus Zorotypus, family Zorotypidae, order Zoraptera. The name is from Latin meaning pure (zor) wingless (ptera).
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