Mesosuchia

†Suborder Mesosuchia Jurassic to Upper Cretaceous; choanae in posterior part of palatine bones. †Suborder Sebecosuchia Upper Cretaceous to Miocene; skull laterally flattened; choanae in depression in anterior part of pterygoids. Suborder Eusuchia Upper Jurassic to

In the Mesosuchia of the Jurassic (201.4 million–145 million years ago) and Cretaceous (145 million–66 million years ago) periods—to which the long-snouted ocean crocodiles also belong—the choanae were already located at the posterior part of two bones of the skull (palatines). In the true crocodiles (Eusuchia), which…