Parapneuroptera
Psocoptera, the bark lice, include 4,400 described species arranged in 3 suborders. There are 50 families of bark lice with over 200 genera. This is the first insect order to show the beginnings of a transition to sucking mouthparts. It is sister group to the Phthiraptera. Bark lice are found on foliage, under bark, or in leaf litter.