Shellfish — edible aquatic invertebrates (culinary term)

Common groups and examples

• Typical edible molluscs include the clam, mussel, oyster and scallop, as well as land snails eaten in some cuisines.
• Frequently consumed crustaceans are shrimp, prawn, lobster, crayfish and crab.
• Some echinoderms, such as the sea cucumber and the sea urchin, are prized regionally but eaten less widely than molluscs or crustaceans.
• Edible cephalopods—including squid, octopus and cuttlefish—are sometimes grouped with shellfish in markets and menus, while terrestrial snails are a related molluscan category found in European and other cuisines.

Different languages and culinary cultures draw the boundary of "shellfish" in distinct ways. For example, in parts of Asia the roe and gonads of various species are important delicacies, and both raw and prepared forms are widespread. Chefs commonly feature shellfish and their roe in dishes such as sushi and sashimi, while other preparations include steaming, frying, grilling, and slow braises.

Uses, nutrition and precautions

Shellfish supply protein, minerals and certain fatty acids and are central to coastal food systems and global trade. They are produced by wild fisheries and by aquaculture; high-volume farmed examples include shrimp and prawn, while bivalve molluscs such as mussels and oysters are commonly cultivated. Consumers should be aware of food-safety risks, including bacterial contamination and toxins from algal blooms.

Shellfish allergy is one of the most common food allergies in adults in many countries and can cause severe reactions; it is distinct from allergies to finfish (finfish) and may not cross-react. Religious and cultural dietary rules also affect shellfish consumption: traditional Jewish dietary law (Jewish) generally prohibits many shellfish, and Islamic rulings (Islamic) vary by school and community, so practices differ worldwide.

Environmental and economic issues are prominent: some high-value species such as lobster, crab and certain sea cucumbers are vulnerable to overharvest, while responsible aquaculture of bivalves can provide sustainable protein with low feed inputs. As a culinary category, "shellfish" remains useful for markets and menus but imprecise biologically—understanding the specific species is important for nutrition, safety and conservation.