Gnathonemus

Gnathonemus is a genus of prehistoric ray-finned fish that lived during the Late Cretaceous period, approximately 99 to 94 million years ago. The genus is known from a single species, Gnathonemus petersi, which was discovered in the Crato Formation of Brazil. Gnathonemus is notable for its unique combination of features, including a large, tooth-filled mouth and a long, slender body. The fish had a single dorsal fin, a large anal fin, and a pair of pelvic fins. Its teeth were conical and serrated, suggesting that it was a predatory species. The genus is of particular interest to paleontologists because it represents one of the earliest known examples of a group of fish known as the teleosts, which are the most diverse and abundant group of living ray-finned fish. The discovery of Gnathonemus has provided valuable insights into the early evolution of teleosts and the diversification of ray-finned fish in general.