Tomognathus was a halecomorph fish related to the modern bowfin that lived in the Cretaceous Period.

It was named by Dixon in 1850.

The name Tomognathus was also later applied to a modern species of ant by Mayr in 1861.

But since the name was already taken it came instead to be classified as Harpagoxenus.

This Amiiformes-related article is a stub.