the silverfish, are of primitive design, appearing in the Devonian. Thysanura
is thought by some to be the linking order between wingless and winged insects.
The compound eyes are small; have three tail bristles on the end of their abdomen;
the mouthparts are external; some species have scales covering the body. After
hatching, the nymphs change to adults with minimal metamorphosis. The young are
similar to adults except in size, molting until sexual maturity is attained. Molting
may continue into adulthood, and there may be more than forty molts in the life
of a thysanuran. There are some 700 named species.
of Fossil Scorpionfly Images
Thysanuran in amber that measures 23 mm including the very long centertail.||Silverfish