The palates of various rhynchocephalians. Bones colorized. In Mesosuchus the palatine is reduced and has lost its teeth. In Hyperodapedon the palatine retains teeth and extends lateral to the choanae to contact the premaxilla. In Howesia the palatine fuses to the maxillary tooth plate. In Trilophosaurus the palatine likewise fuses to the maxillary tooth plate and the palatine teeth fuse to the maxillary teeth, creating laterally elongated teeth with three lateral cusps.

In Howesia and Mesosuchus I rotated the ectopterygoid from a jugal articulation to a maxilla articulation, contra Dilkes (1995, 1998), to match sister taxa.
The right ectopterygoid in the Howesia figure is not rotated.