What is the Difference Between Crustaceans and Molluscs (Mollusks)?
🆚 Go to Comparative Table 🆚Crustaceans and mollusks are both types of shellfish, but they have distinct differences in their structure and biology. Here are the main differences between the two:
Crustaceans:
- Aquatic animals with jointed legs, a hard shell, and no backbone.
- Examples include crab, crayfish, lobster, prawns, and shrimp.
- Their body is segmented into the abdomen and cephalothorax.
- They have a chitinous exoskeleton.
- They have biramous appendages.
- Most crustaceans are free-living aquatic organisms, while some are terrestrial.
Mollusks (Molluscs):
- Soft-bodied invertebrates covered in a calcareous shell.
- Examples include clams, mussels, oysters, scallops, octopus, snail, and squid.
- They have soft, unsegmented bodies.
- They have a muscular foot and a visceral hump.
- They do not have biramous appendages.
- They can live in both land and sea environments.
In summary, crustaceans have a hard shell and jointed legs, while mollusks have a soft body and a calcareous shell. Crustaceans are segmented, while mollusks are unsegmented. Crustaceans have biramous appendages, while mollusks do not.
Comparative Table: Crustaceans vs Molluscs (Mollusks)
Crustaceans and mollusks are two distinct groups of invertebrate animals that belong to the phylum Arthropoda and the phylum Mollusca, respectively. Here is a table summarizing their main differences:
Feature | Crustaceans | Mollusks |
---|---|---|
Taxonomy | Subgroup under the phylum Arthropoda | Second largest phylum in the Animal kingdom |
Body Structure | Segmented into abdomen and cephalothorax | Soft, unsegmented bodies |
Exoskeleton | Chitinous exoskeleton | Calcareous shell |
Appendages | Biramous appendages | No biramous appendages |
Muscular Foot | No muscular foot or visceral hump | Muscular foot and visceral hump |
Examples | Lobsters, crayfish, crabs, shrimps, prawns, barnacles, amphipods, copepods, etc. | Apple snail, cuttlefish, pearl oyster, squid, etc. |
Crustaceans are characterized by their segmented bodies, chitinous exoskeletons, and biramous appendages. On the other hand, mollusks have soft, unsegmented bodies, calcareous shells, and no biramous appendages. They also possess a muscular foot and a visceral hump, which are absent in crustaceans.
- Shellfish vs Crustaceans
- Mollusks vs Arthropods
- Arachnids vs Crustaceans
- Mollusca vs Echinodermata
- Lobster vs Crayfish
- Crayfish vs Crawfish
- Lobster vs Crab
- Mussels vs Clams
- Lobster vs Shrimp
- Clams vs Oysters
- Cephalopods vs Gastropods
- Mussels vs Oysters
- Prawns vs Shrimps
- Prawn vs Lobster
- Slugs vs Snails
- Male vs Female Crabs
- Lice vs Crabs
- Male vs Female Crayfish
- Cuttlefish vs Squid