proturan
any of a group of about 150 species of minute (0.5 to 2 mm [0.02 to 0.08 inch]), pale, wingless, blind, primitive insects that live in damp humus and soil and feed on decaying organic matter. Proturans, frequently known as telsontails, include some of the most primitive hexapods (i.e., animals with six legs). They are worldwide in distribution, although the group was unknown before 1907.
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