Cephalaspis

Good

Characteristics
This fish was suggested to be one of the first to use memory to get back to their spawning pool to reproduce like Salmon shit (But there is no proof). It was the size of a goldfish and, at the largest, a trout.

Other information
Cephalaspis's main predators were probably Brontoscorpio or pterygotus. Although it had no jaw and sucked up algae through it's mouth, it is thought to be an ancestor of jawed fish and amphibians.