This is the Canvey Island Monster. I created this cryptid creature / monster art for Fairytales and Myths.
The Canvey Island Monster is an unidentified marine species whose carcass washed up on Canvey Island, Essex County, England, in the 1950s.
Creating this creature art was a bit difficult since the real-life reference images were all literally misshapen corpses. So, I followed the prevailing artistic trend, which was to depict the creature as a fish with two legs.
Check out the Canvey Island Monster page for more details.