In a recent study published in Historical Biology, researchers describe a new large prehistoric shark (Megalolamna paradoxodon gen. nov. et sp. nov.).
The new species is based on isolated teeth found from the Jewett Sand in southern California, the Pungo River Formation of North Carolina, the Chilcatay Formation of Peru, the Oi Formation and the O’oshimojo Formation in Japan.
Researchers from DePaul University in Chicago, North Carolina State University, The University of Hong Kong, and The Japanese Club for Fossil Shark Tooth Research conducted the study.
Based on available published data on modern sharks, researchers suggested that the largest specimen of this type of shark is possibly from a shark that measured at least 3.7 meters in total length.
All specimens came from deposits in the mid-latitudinal zones and suggested the shark lived in a shallow-water, shelf-type, coastal environment. The teeth showed that the shark could capture and cut medium-sized fishes.
Researchers suggest that the global distribution of the prehistoric shark is remarkable given the large size of the shark. In addition, the new finding adds new evidence for the shark evolution process.
Citation: Shimada K, et al. (2016). A new elusive otodontid shark (Lamniformes: Otodontidae) from the lower Miocene, and comments on the taxonomy of otodontid genera, including the ‘megatoothed’ clade. Historical Biology, published online. doi: 10.1080/08912963.2016.1236795.
Figure legend: This Knowridge.com image is credited to Shimada K et al.