Can you name an extinct species of fish?

The coelacanth is a well-known example of an extinct fish. It was thought to have gone extinct 65 million years ago but was found to still be extant in 1938. However, there are many extinct fish species that are not still extant, such as the giant ground shark Megalodon, which reached lengths of up to 59 feet and is estimated to have become extinct about 2.6 million years ago.