 Pseudosuchia as used in recent literature is a stem-based taxon that includes crocodile-line archosaurs, or all archosaurs (including crocodilians) that are more closely related to crocodilians than birds.Robert Carroll, in his book "Vertebrate Paleontology and Evolution" (1988), replaces Pseudosuchia with Rauisuchia, Ornithosuchia, and the traditional category "incertae sedis" (of uncertain placement), while retaining the other three suborders.This is the last major textbook that still recognizes the taxon Thecodontia, as it uses a traditional Linnaean based taxonomy.