Elegestolepis

Elegestolepis is a primitive shark that lived during the Silurian and Devonian periods. It was closely related to Mongolepis and Polymerolepis. It is only known from placoid scales discovered in Russia before 1973. The oldest of these scales have been dated back to the Ludlow epoch, making Elegestolepis the oldest known shark.

Although only known from placoid scales Elegestolepis, along with Mongolepis and Polymerolepis, is the oldest confirmed shark known to science. Elegestolepis dates back to about four hundred and twenty million years ago, but some scales that may yet represent another shark ancestor are known from four hundred and fifty million years ago. Although the placoid scales are accepted to be those of a shark, subtle differences in the scales suggest that Elegestolepis itself may have been quite different in appearance to modern sharks.