Scientists have solved the mystery of a prehistoric creature with a mouth and no anus.

S. coronarius had a large, round mouth with tiny holes around its perimeter. At first, scientists thought they were primitive gills. But it turned out that the pores were the bases of spikes that broke off during the formation of fossils. With these outgrowths, the creature held prey. The researchers explained the mysterious absence of the anus by the fact that the animal lost it in the course of evolution - one hole was enough for him to satisfy all his needs.