Difference Between Crayfish and Lobster

The main difference between crayfish and lobster is that the crayfish lives in freshwater including rivers, streams, lakes, and ponds whereas the lobster lives in saltwater including oceans and the sea. Furthermore, crayfish are generally small while lobsters are comparatively large. 

Crayfish and lobster are two types of crustaceans that belong to the order Decapoda. They are famous due to their divine taste as seafood. 

Key Areas Covered 

1. Crayfish
     – Definition, Characteristics, Behavior
2. Lobster
     – Definition, Characteristics, Behavior
3. What are the Similarities Between Crayfish and Lobster
     – Outline of Common Features
4. What is the Difference Between Crayfish and Lobster
     – Comparison of Key Differences

Key Terms 

Crayfish, Crustaceans, Front Claws, Lobster, Rock Lobsters

Crayfish – Definition, Characteristics, Behavior 

Crayfish is a freshwater decapod with large, edible, front claws. It is much smaller than their saltwater relatives, the lobsters. A crayfish can grow up to 2-6 inches long. It lives in rivers, dams, or lakes, eating whatever they find on the muddy bottom. The largest freshwater invertebrate in the world is the Tasmanian giant freshwater crayfish (Astacopsis gouldi) that lives in Australia. Apart from that, the most common crayfish in Australia is the Yabby. Murray is another one of the large species of crayfish.  

Figure 1: Cambarus Scotti (Chattooga River Crayfish)

Crayfish can tolerate wide ranges of salinity and water temperatures. They can even be alive when their water sources have been completely dried up. However, they are very intolerant to pollution. 

Lobster – Definition, Characteristics, Behavior 

Lobster is a saltwater decapod with similar front claws. The most common variety in Europe is the European or Breton lobster (H. gammarus) that is blue in color while the American lobster (H. americanus) found in Northern America is brown or green in color. Australian relations of the lobsters are the rock lobsters and this variety has much smaller front claws. Sometimes, rock lobsters are called spiny lobsters. In the USA, rock lobsters are known as crayfish. Thus, lobsters with these large claws are called ‘true lobsters’. The most colorful lobsters are the reef lobsters that live in the rocky,coral reefs in the warmer parts of the Atlantic Ocean, Caribbean Sea, and Indo-Pacific Ocean. They are red, orange or purple in color and have rings, spots or strips.  

Figure 2: European Lobster (Hommarus gammarus)

Generally, lobsters are larger than crayfish and can grow up to more than 20 inches. However, when lobsters are harvested for food, they are at least eight inches long. Lobsters prefer small ocean animals and sometimes, they become scavengers. The flavor and the texture of squat lobster are similar to that of shrimps. Unless otherwise, both the taste and the texture of crayfish and lobster is equal.  

Similarities Between Crayfish and Lobster 

• Crayfish and lobster are two types of aquatic crustaceans that belong to the order Decapoda. 
• They have five pairs of legs and five pairs of swimmerets.  
• Their front leg pair is differentiated into two, large claws, which help them to defend and catch the prey. 
• Both have antennae and a long tail. Also, they have a pair of compound eyes. 
• They have a tough exoskeleton, covering their body made up of chitin. 
• The two body segments of crayfish and lobster are the cephalothorax and abdomen. Their abdomen is made up of several segmented stacks. 
• They prefer to live in the bottom of the water, hiding under rocks or crevices. 
• The taste and the texture of both types are similar. 

Difference Between Crayfish and Lobster 

Definition 

Crayfish refers to a nocturnal freshwater crustacean that resembles a small lobster and inhabits streams and rivers while lobster refers to a large marine crustacean with a cylindrical body, stalked eyes, and the first of its five pairs of limbs modified as pincers. 

Family 

The crayfish belong to three families: Cambaridae, Astacidae, Parastacidae while lobster belongs to the family Palinuridae. 

Geographical Location 

Crayfish live mainly in Northern America but is found in all parts of the world while lobsters live in Europe, Northern America, and Australia. 

Habitat 

Furthermore, the crayfish live in freshwater while lobsters live in saltwater.

Size  

The crayfish is smaller while the lobster is comparatively large. 

Color 

Also, the crayfish can be greenish color while lobsters are very colorful. 

Diet 

Crayfish eat worms, insects, and plants while lobsters eat small fish, prawns, clams, and snails. 

Conclusion 

Crayfish is a small freshwater decapod with large front claws while lobster is a comparatively large, saltwater decapod with large front claws. Crayfish is not much colorful while lobsters are colorful. The main difference between crayfish and lobster is their size and their habitat. 

Reference:

1. “Lobsters, Rock Lobsters and Crayfish.” Western Australian Museum, Available Here

Image Courtesy:

1. “Chattooga River Crayfish” By U.S. Fish and Wildlife Service Southeast Region (CC BY 2.0) via Flickr
2. “KreeftbijDenOsse” By Bart Braun – Own work (Public Domain) via Commons Wikimedia