Pachyrhizodontidae

Rhacolepis is an extinct genus of ray-finned fish from the Cretaceous Romualdo Formation of Brazil. Complete fossilised hearts from this species have been recovered.thumb|R. buccalis skull|leftleft|thumb|Inside the stomach of a Notelops|Notelops brama. left|thumb|R. buccalis with several hundred small shrimp in stomach. thumb|Fossil in Vienna

Pachyrhizodus is an extinct genus of ray-finned fish that lived during the Cretaceous to Paleocene in what is now Europe, North America, South America, and Oceania. Many species are known, primarily from the Cretaceous of England and the midwestern United States.