There is a white ivory sea creature. What creature is it?

Ivory mussel (scientific name: Panopea abrupta): The biological name is Pacific cement clam, also known as emperor mussel and goddess mussel, and the seafood trade name is "Ivory mussel". The two shells are the same size, thin and brittle, with serrations, sub-shells and water pipes (also called tentacles) at the front end.

It is an advanced seafood advocated by China and Japanese in the Far East. Native to the North Pacific coast of the United States and Canada. Because of its big fleshy red tube, it looks like an elephant's nose (like a mussel), so it is called "like a mussel". The locals don't eat mussels, so they grow well. However, since Asian immigrants began to prey on North American mussels, local mussels have been on the verge of extinction. 1996, artificial cultivation began in China market.