It looks like a grape, lives in the ocean, moves really slowly, and it's actually a huge single-celled organism at 1 inch. It's the Bahamian Gromia.
The sea grape may be one of the slowest-moving creatures on earth. They leave tracks in the deep sea mud where they live, but scientists couldn't see them move. Now the idea is that they move really slowly, like 1 inch per day.
The sea grape may be responsible for fossil tracks made 530 million years ago, roiling the waters of how scientists view ancient life. The tracks were too complex to be made by simple single-celled organisms, or so we thought until we learned about the sea grape.
That's a lot of new thinking for a creature originally called doo-doo balls because they were thought to be some sort of poop.