What is the Difference Between Shellfish and Crustaceans?

The terms "shellfish" and "crustaceans" are often used to describe a variety of aquatic animals with exoskeletons. While crustaceans are always shellfish, not all shellfish are crustaceans. The main difference between the two lies in their limbs and how they develop.

Crustaceans:

• Characterized by hard outer shells and segmented limbs.
• Examples include shrimp, crab, lobster, prawns, crayfish, krill, and barnacles.
• Develop from larvae.

Shellfish:

• A broad term used for crustaceans and mollusks with exoskeletons or calcareous shells.
• Can be divided into two main categories: crustaceans and mollusks.
• Mollusks are soft-bodied invertebrates with calcium carbonate shells, examples include clams, mussels, scallops, oysters, and cockles.

In summary, crustaceans are a type of shellfish with hard outer shells and segmented limbs, while shellfish is a broader term that encompasses both crustaceans and mollusks, which have either chitinous or calcareous exoskeletons.

Comparative Table: Shellfish vs Crustaceans

The terms "shellfish" and "crustaceans" are often used to describe aquatic invertebrates with exoskeletons. While crustaceans are always shellfish, not all shellfish are crustaceans. Shellfish can be divided into two main categories: crustaceans and mollusks. Here is a table highlighting the differences between shellfish and crustaceans:

Some key differences between crustaceans and mollusks include:

• Crustaceans have a hard outer shell and segmented limbs, while mollusks have a soft body and a calcium carbonate shell.
• Crustaceans are a type of arthropod with a prominent cephalothorax and abdomen, while mollusks are soft-bodied invertebrates.
• Examples of crustaceans include shrimp, crab, and lobster, while examples of mollusks include clams, mussels, scallops, and oysters.

Both crustaceans and mollusks are important as food sources for humans, but they belong to different taxonomic groups and have distinct characteristics.