The 9 Most Popular Types of Shellfish
The diverse world of shellfish is almost as vast as the oceans themselves. Shellfish as a seafood category encompasses the many species of crustaceans (the varieties with legs that help them swim or crawl, like lobsters, shrimp, and crabs) and bivalves (the hard-shelled and more stationary varieties like clams, oysters, and mussels).
Fun fact: Cephalopods like octopus, squid, and cuttlefish are also technically shellfish despite their lack of external shells, as they fall within the mollusk family.
These nine popular types of shellfish are harvested and grown throughout the United States, so you’ll always have an excuse to indulge in your favorite. When it comes to getting the freshest shellfish, “Find a reliable fish market,” says John Carson, retired commercial fisherman and farmstand owner on the North Shore of Long Island, New York. “Apart from going out and catching it yourself, you’re not going to do any better.”
Types of Shellfish
Shrimp are crustaceans with exterior shells that are flexible and easy to peel off when you’re prepping and eating them. With approximately 2,000 different species of shrimp out there, it’s not surprising that you’ll find these tender-textured swimmers all over the world in both warm and cold, as well as fresh and saline, bodies of water.
In the U.S., most wild-caught shrimp comes from the Gulf of Mexico, and white, pink, and brown shrimp are likely what you’ll be consuming from this region. Historically, “Maine is famous for its red shrimp,” Carson notes, referring to the small Northern shrimp that are found throughout the cold waters off the Northeast coastline. However, commercial fishing of Northern shrimp has been prohibited for a few years because of low population numbers.
Scallops are bivalve mollusks featuring a round, saucer-like shell with fluted (or scalloped!) edges. When we eat bivalves like scallops, oysters, clams, and mussels, we’re actually eating the adductor muscle inside the shell that helps it hinge open and closed.
The two most popular varieties of scallops are bay and sea scallops, differentiated by their size and habitat. “There are no bay scallops that live in the ocean and no sea scallops that live in the bay,” Carson said.
Bay scallops are the smaller, popcorn-size variety that are great for tossing into dishes like pasta. Sea scallops are the larger version, typically seared and served as the main ingredient of a dish. Both are very delicate in both flavor and texture, with a briny sweetness.
While the Northeastern U.S. is prime ground for sea scallops, “Bay scallops can grow in warm water,” Carson said, so you’ll find them in the Middle Atlantic all the way down to Florida, where a variety known as Calico scallops are harvested.
Lobster is the crustacean that’s most synonymous with Maine and New England, although various species can be found in oceans all over the world. The hard-shell lobster we know best, which turns bright red when cooked, is Homarus americanus, the American lobster.
Although lobsters are harvested from their rocky bottom-dwelling habitats all year, the latter half of the year is considered to be lobster season. That’s when the lobsters will be at their largest with the most meat for picking.
Crabs, like shrimp, are crustaceans with a large and diverse population, found in both salt and fresh water. The crabs we love to eat mostly have a hard shell known as a carapace and large front claws, or pincers. (Hermit crabs are indeed crabs!) They can range widely in size, from enormous Alaskan snow and king crab to smaller East Coast blue crabs — perfect for seasoning with Old Bay.
Other popular crab varieties include Dungeness in the Pacific Northwest, stone crab (of which we only eat the claws) in Florida and the South, peekytoe or rock crab along the East Coast, and Jonah crab in Maine.
Mussels are another variety of bivalve mollusk. Marine blue mussels, which attach to rocks and other surfaces in the intertidal shallow areas along saltwater coastlines, are the ones with a shiny black oval shell and a very soft and sweet inner edible muscle. (Freshwater mussels are generally more popular with otters than humans!)
Like many shellfish, mussels are found around the world, with two of the most popular growing regions being Prince Edward Island in the North Atlantic and the Pacific Northwest waters around Washington and British Columbia. Although they can be harvested wild, farmed mussels are becoming increasingly popular.
Oysters are the bivalve that’s most frequently eaten raw. With their craggy shells and succulent, briny meat, oysters get their flavor from the salt water they grow in. American oysters can be found all along the East and West coasts, most commonly in the Pacific Northwest and the Northeast. However, oysters also thrive in the Chesapeake Bay region, the Gulf Coast, and the Bay Area of California.
The old adage of only eating oysters in months that end in the letter R came about in the days before mass refrigeration, which also dissuaded people from eating wild oysters during their warm-water spawning season. Now, as oyster farms have proliferated along both coasts and food safety regulations are in place, it’s fine for people to eat oysters year-round, according to Carson.
Clams are the bivalves that rule the New England coastline, competing with lobster as the region’s most beloved shellfish. However, their territory extends along both Atlantic and Pacific shorelines, where they dig into the sand along many beaches and intertidal zones. Clams are available year-round as a wild harvested food.
“Most people are familiar with hard clams, which have an assortment of different names,” Carson said. Quahogs, littlenecks, cherrystones, and chowders refer to different sizes of the same clam variety. Steamers are slightly larger with softer shells, and surf clams are frequently sliced up for fried clam strips.
On the Pacific coast, Manila clams are tiny with purple-mottled shells, geoducks are characterized by their nearly obscene protruding siphon (often sliced for sushi). and razor clams are the outliers of the clam fam with long, thin oblong shells.
Crawfish, or crayfish or crawdads depending on where you live, look like tiny lobsters with their chunky claws. These small crustaceans are not genetically lobsters, because they live in freshwater rivers, streams, and ponds instead of saline bodies of water. However, crawfish have a similar taste and texture to lobster when cooked.
In Southern Gulf states like Louisiana, where crawfish are commonly found, the season for peak eating is in late winter through spring. Because they are wild and not farmed, the season varies based on weather conditions.
Prawns are very similar to shrimp in taste and texture, altthough they belong to different sub-orders, biologically speaking. Prawns only live in fresh water and tend to be larger than shrimp and won’t curl up into a C shape like a shrimp does when cooked.