Articles relating to the Trogiomorpha, one of the three major suborders of barklice, booklice, and parasitic lice in the order Psocodea (formerly Psocoptera), alongside Troctomorpha and Psocomorpha. There are about 8 families and more than 430 described species in Trogiomorpha. Trogiomorpha is widely agreed to be the earliest diverging of the three suborders, and retains the most primitive characteristics.