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New Species of Fish Discovered Through Texan Fossil

Everything’s bigger in Texas—including the archeological discoveries.

In 2014, Kenshu Shimada, Ph.D., professor at Chicago’s DePaul University and research associate to Sternberg Museum in Kansas, made a peculiar discovery at the Perot Museum of Nature and Science in Dallas, Texas. A fish fossil on display at the museum appeared to be different than those that he’d seen before.

“At first glance, the specimen looked like a known Pentanogmius species, but when I began to trace the curved dorsal fin, its front half kept extending backwards far beyond where I thought it would end relative to its rear half. That’s when I realized I have something new to science,” said Dr. Shimada in an interview with

After extensive research, Shimada discovered that the 5.5-foot-long and 90-million-year-old fossil did, in fact, belong to a new species. It’s now called the “Pentanogmius fritschi” and is named as such to honor amateur fossil collector Joseph Fritsch, the man who discovered it. Fritsch, alongside fellow collector Kris Howe, dug this specimen up when he was exploring the Britton Formation part of the Eagle Ford Shale—which is located in Dallas County. Fritsch and Howe would later donate the fossil to the Perot Museum.

According to Shimada’s research, the Pentanogmius fritschi sustained itself by eating smaller fish and squid and lived primarily in open ocean environments. It’s body is similar to that of a tuna fish and it sports a particularly unique ‘hook-shaped sail’ on its back. The research is currently set to feature in an upcoming issue of Cretaceous Research, an international scientific journal.

The Eagle Ford Shale has long been a region rife with fossils and impressive archeological encounters. The region is considered a sedimentary rock formation from the Late Cretaceous era that spans much of the South Texas area. Much of the sediment contains organic marine shale that’s very rich in fossils from ancient sea life. It’s broken up into three sub-units: the aforementioned Britton Formation, the Tarrant Formation, and the Arcadia Park Formation.
Other fossils found in the Britton Formation include various plesiosaurs remains, pterosaur remains, and hundreds of other ancient fish species.