any one of a group of extinct sharks from Oligocene to Pleistocene epochs
An extinct genus of Pelecypoda typifying the household Megalodontidæ. It really is characterized by ponderous heart-shaped shells with amphidetic location, opisthodetic ligament, and enormous and heavy cardinal teeth. The earliest species are Devonian, nevertheless shells tend to be many rich in the Triassic stones. Correctly Megalodus.