A ship is a large watercraft that travels the world's oceans and other sufficiently deep waterways, carrying goods or passengers, or in support of specialized missions, such as defense, research, and fishing. Ships are generally distinguished from boats, based on size, shape, load capacity, and tradition.
This page lumps together representatives from crustaceans and mollusks. Freshwater typically has lower diversity than the ocean. However, this is just a tiny sample of what may be found.