Whelk (trumpeters or buccinidae).

Whelk is a carnivore. It feeds on carrion, decay products, bivalve molluscs, benthal echinoderms, worms, small fish and even other snails (this is the most easily-accessible food for the slow-moving mollusc). It has a stunningly keen sense of smell.
The mollusc will move by the sense of smell until it catches up with its prey. The gastropod whelk is considered the main enemy for mussel settlements that cannot stand up to this carnivore. In 2—3 hours, an adult snail is able to eat one individual, and in 10 days it reduces a mussel settlement by more than 100 units.
The mollusc is considered seafood delicatessen. Its meat is very tasty, nourishing, but at the same time low-calorie
The nutrition value per 100 grams of the mollusc flesh is 17 grams of pure protein, 3 grams of carbohydrates and only 0.5 grams of fat. The total energy content of the product is 24 kcal. Whelk flesh is rich in vitamins, mostly of group B, iodine and fluorine.
The mollusc is considered one of the most ancient animals on Earth. Fossil snails are attributed to the first Caenozoic Era — the beginning of the Paleogene.