Chubutensis

Chubutensis Sharks are part of the Otodus family just like the Megalodon. The Chubs are older and went extinct 22 to 28 Million years ago.  One of the defining characteristics of a CHUB is as the blade connects to the root you will see a small flaring.  This flaring is related to the ancestor (Angustiden) of the Chubutensis having smalls cusps and the Megalodon not having any at all.  The Chub was a transition from Angustiden to Megalodon!