Britannica
Sources used in this answer
Which animals belong to the class Malacostraca?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
malacostracan
Hermit crab (Pagurus samuelis).
The class Malacostraca is the largest group within the subphylum Crustacea, comprising more than 29,000 living species of invertebrates. These animals are found in diverse environments, including marine, freshwater, and terrestrial habitats.12
Common animals that belong to the class Malacostraca include:
- Decapoda: The largest order, which includes lobsters, crayfish, shrimp, crabs, and hermit crabs.12
- Isopoda: A major group of crustaceans that are widespread in marine, freshwater, and terrestrial environments.12
- Amphipoda: A group of over 6,000 species abundant in marine shores, deep-sea environments, and fresh waters.1
- Other groups: The class also includes Stomatopods, tanaids, cumaceans, and mysids.1
Malacostracans are distinguished by their evolutionary success, characterized by specialized body regions, sophisticated food-gathering appendages, and a wide range of sizes and forms.2