Eurypterus remipes, with frame, Siluria Deinonychus populator skull rivaling it in

populator skull rivaling it in size

are the most common and abundant

Bothriolepis belongs to a now-extinct group of primitive-jawed armored fish called Placodermi

Eryops may have been slow moving on land

Eurypterus remipes, with frame, Siluria Deinonychus populator skull rivaling it inEurypterids, or water scorpions, were aquatic predators that thrived until the end of the Paleozoic Era for about 250 million years. Eurypterids primarily lived in brackish water in lagoons and estuaries, feeding on everything from mollusks to primitive fish. According to fossil trackways found in Australia, eurypterids could also spend time on land, and were likely the first animals to leave the water. Eurypterids are part of an extinct order of