Knightia Eocaena <br> from the USA <br> 48 million years

Knightia is an extinct genus of schooling, ray-finned, spindle-shaped, bony fish that shares a family with herrings and sardines. They lived in the freshwater (lacustrine) environments of North America and were eaten by just about everything that was bigger. They ate insects and smaller fish, and used gill rakers to feast on plankton. Knightia eocena is the largest of three species of Knightia, with a typical length of about 15 centimeters.

They have rows of dorsal and ventral scutes which ran from the back of the head to the medial fins. They had heavy scales, and small conical teeth, and were a primary food source to the large and hungry vertebrates that once lived in the Green River.