Bananogmius is an extinct genus of marine ray-finned fish that was found in what is now North America and Europe during the Late Cretaceous, from the Cenomanian to the Santonian.

[1] It lived in the Western Interior Seaway, which split North America in two during the Late Cretaceous, as well as the proto-North Sea of Europe.

Further analysis of Cope's description of the original Anogmius contractus confirms that it was a plethodid and not a pachyrhizodontid, but this specimen was too fragmentary for a proper diagnosis and is now lost, leaving Bananogmius as the valid name.

[9] As with many plethodids, Bananogmius had a thin body reminiscent of the modern angelfish, dozens of small teeth, and a high dorsal fin.

A fossil of B. ornatus from Germany from around the Cenomanian-Turonian boundary is preserved with the skeletons of the small schooling fish Clupavus in its stomach.