The strange creature is still waiting for a definitive classification, since science is not decided regarding this species. Was it vertebrate or invertebrate?
The ‘Tully Monster‘ ( Tullimonstrum gregarium) is a species of underwater slug with two antennae crowned by eyes and a long trunk ending in a mouthful of sharp teeth. We know that this strange alien-looking sea monster inhabited the depths of Earth some 300 million years ago in the waters that currently make up the state of Illinois...
http://www.maritimeherald.com/2020/what-is-the-monster-of-tully/