This image is of some fossil teeth of the Mako shark aka
Isurus planus (Agassiz, 1856) on display at Mace Brown Museum of Natural History (August 2017). It dates to the Miocene Epoch (about 15 million years ago) of the Neogene Period. The fossils were found in Brown Mountain slit layer of Bakersfield, California USA. It appears the genus was renamed in 2021 to
Cosmopolitodus (Glikman, 1964) an extinct mackerel shark.
The Mace Brown Museum of Natural History is located at the College of Charleston, 202 Calhoun Street, 2nd Floor, Charleston, South Carolina 29424.
Learn more at their blog:
http://blogs.cofc.edu/macebrownmuseum/