A previously undiscovered shark species dating back over 90 million years ago was recently discovered in an ancient seabed in modern-day Kansas.
The partial remains of the newly named Cretodus houghtonorum, which is believed to be nearly 20 feet in length, was discovered in the region known as the Western Interior Seaway in 2010 at a ranch near Tipton, Kansas. Research associates Kenshu Shimada and Michael Everhart of the Sternberg Museum of Natural History at Fort Hays State University identified the new specimen which was named after the ranchers Keith and Deborah Houghton, the landowners who donated the specimen to the museum for science.
Analysis of the 134 teeth, 61 vertebrae, 23 placoid scales and fragments of calcified cartilage provided anatomical data that suggested the new shark was a rather sluggish shark that belonged to the group, Lamniformes, which includes modern-day great white and sand tiger sharks.
“Much of what we know about extinct sharks is based on isolated teeth, but an associated specimen representing a single shark individual like the one we describe provides a wealth of anatomical information that in turn offers better insights into its ecology,” said Shimada, the lead author on the study. “As important ecological components in marine ecosystems, understanding about sharks in the past and present is critical to evaluate the roles they have played in their environments and biodiversity through time, and more importantly how they may affect the future marine ecosystem if they become extinct.”
The fossils of the new species was found along with isolated teeth of another shark, Squalicorax, as well as with fragments of two fin spines of a yet another shark, a hybodont shark.
“Circumstantially, we think the shark possibly fed on the much smaller hybodont and was in turn scavenged by Squalicorax after its death,” said Everhart.
The findings were detailed in the latest issue of the Journal of Vertebrate Paleontology.