Odontognatha (lit. "toothed jaws") are a clade of Deinognatha, consisting of all semiaquatic and fully aquatic Deinognathans.
Odontognathans first emerged around 4215ma, evolving from Deinognathans who utilized riverbanks as hunting grounds. Over the next 35 million years, various lineages of Odontognathans have evolved a variety of lifestyles, although a number of traits have remained consistent among them.
Odontognathans live either semi-aquatic or (in the case of the Thalattotheria clade) fully aquatic lifestyles. Their eyes are located near their cephalothorax, while their spiracles are located on their upper abdomen.