Great job! Another evolution! This shark was characterized by broad-based paired fins, a short stout bony spine preceding the first of the two dorsal fins, and a large lunate tail-fin.Unlike larger forms, its mouth opened at the front of the skull, rather than beneath it, and both its pectoral and pelvic fins were broadly attached to its body. An adult would grow upto 1.8 metres (5.9 ft) long. You’ve now successfully made it a step closer to the modern shark! Prey population has began to increase.