The coelacanth has one of the longest lineages -- 400 million years -- of any animal, and they were thought to have gone extinct 70 million years ago until live specimens were caught off the coast of Africa in 1938. Today, they can be found swimming in the depths of the Indian Ocean.
The coelacanth is often called a "living fossil" because it has not evolved significantly since reaching its current form about 400 million years ago.
Southern Methodist University paleontology graduate student John F. Graf discovered the Texas fossil, the first found in the state that has been dated to the Cretaceous period extending from 146 million years ago to 66 million years ago.
The new species, found in ancient marine sediments in North Texas and dubbed Reidus hilli, is now the youngest coelacanth fossil identified in the Lone Star State, he said.
Previously the youngest was a 200-million-year-old coelacanth from the Triassic.
"What makes the coelacanth interesting is that they are literally the closest living fish to all the vertebrates that are living on land," Graf said. "They share the most recent common ancestor with all of terrestrial vertebrates."
While coelacanth fossils have been found on every continent except Antarctica, few have been found in Texas, an SMU release said.