“Mirrored jaw”

The Enoptrognathidae is currently described from one species, and until recently was considered to possibly be a mutated Toxodentid or Tridentid. Though considered to be closely related to the Tridentidae, The structure of the Enoptrognath oral groove is nearly a total inverse reflection of Tridentid oral grooves. Squared oral hooks are separated from the deeper groove by downward-curving dential processes, with a sloped process at its center.