Trachygnatha (lit. "jagged jaws") are a clade of semiaquatic Deinognatha.
Trachygnathans first emerged around 4217ma, although it is largely similar to the early Odontognathans in terms of anatomy and lifestyle.
Trachygnathans are the apex predators of the equatorial swamps, hunting terrestrial prey alongside the river banks as well as semi-aquatic animals, such as the Prenobrachids. They are the only observed clade of Odontognatha to retain the robust jaws of early Deinognatha, which are useful for restraining prey in the water.