Commonly called bark lice or book lice or barl lice, the Psocopterans sport membranous wings held roof-like over abdomen. The order is thought to have appeared in the Permian, and some 6000 extant species have been described.

Gallery of Fossil Psocoptera (Bark or Book Lice) Images
Psocoptera in fossil amber Pliocene to Pleistocene Andes Mountains, Colombia	Psocoptera in fossil amber Pliocene to Pleistocene Andes Mountains, Colombia The circular wing morphology of this specimen differentiates it form the normally seen Bark Lice.	Psocoptera in fossil amber Pliocene to Pleistocene Andes Mountains, Colombia