Hoplopteryx

Hoplopteryx is an extinct genus of Trachichthyidae from the Cretaceous.

Biology
Hoplopteryx has a dorsal fin supported by nine unjointed, bony rays, deeply forked, homocercal tail, a moderately developed anal fin, and a pelvic fin located well forward. The snout is quite short, the eyes fairly large, and both jaws of the upturned mouth hold small teeth.

Habitat
Hoplopteryx was a marine fish, living in shallow chalk seas.