This order of wingless insects consists of about 350 known species. They hide under bark, in litter, and in rock crevices, and feed on algae, lichens, and vegetable debris.

  Oldest fossil considered as Archaeognatha is from the Devonian (390 million years old) from Gaspé, Québec (Labandeira et al., 1988). However, there is little evidence that this fossil is a member of Archaeognatha; it may instead be a member of the stem-group of insects or of stem-Dicondylia.