Carcharodon hastalis : Mexico

This catalog contains exceptional teeth from the big-tooth Mako shark - Carcarodon (Isurus) hastalis. The upper jaw teeth are noted for their well defined triangular crown and broad roots (upper jaw) while the lower jaw teeth exhibit  slender crowns - all  without serrations. Complete lower jaw teeth are hard to find since they are much more fragile. Miocene age (15 million years ago). These teeth are from a very old collection of rare Baja, Mexico shark teeth.

What’s in a name? For the fifty years, Isurus hastalis was known to me and others as the Big-tooth Mako shark tooth that collectors sought from Miocene – Pliocene deposits. Everyone wanted to find a big Mako tooth. In 2001, Purdy (Smithsonsian) resurrected Isurus xiphodon for the broad-form Mako teeth at Lee Creek. It made sense, but now it is not considered a valid species. In 1964, Glikman proposed the Cosmopolitodus genus for the "hastalis" shark as Isurus hastalis was related to the Great White shark rather than the Mako. This convention was not adopted in the scientific community until the last decade; particularly with the naming of the Carcharodon hubbelli, the Great White transition tooth (late Miocene). There is also a push to rename the genus of the shark formerly known as Isurus hastalis to Carcharodon hastalis recognizing that it is an early form of the Great White shark. Ok, Isurus hastalis and Isurus xiphodon names going away, but the future genus name for "hastlis" appears to be unsettled. What do we call this shark if it is not a Mako? More to come in my Blog article.