Man eating Tulips found in Burgess Shale

This massive tulip shaped creature roamed the world gorging itself on man and beast in a ravenous rampage.

Roar.

Ok, that's my fanciful take. Its not quite massive, being the size of a dinner knife, it couldn't have roamed much being anchored to the ocean floor, and likely could not have eaten much but plankton and such and even lived long before man graced the world with his presence. It did look like a tulip.