Troctomorpha (Book Louse) is a suborder of Psocodea. There are 5432 species of Book Louse, in 394 genera and 33 families. This suborder has been around since the callovian age. It includes groups like Lice.
Definition: The number of fossil occurrences in the Paleobiology Database (https://paleobiodb.org) that are identified as belonging to a particular taxon or any of its subtaxa.