Fossilized fish tooth of a Xiphactinus or X-fish.

A fossilized fish tooth of a Xiphactinus vetus or X-fish from the Blufftown Formation in Barbour County, Alabama, USA. The species of X-fish was originally misidentified as a mosasaur under the species, Polygonodon vetus.

#fish #fossil #paleontology #xiphactinus #polygonodon