Key difference: Prawns and fishes are similar in their looks and features as both have fins, however prawns are not fishes. Prawn is a crustacean, identified by its shell and lack of a spine, whereas fishes can be identified by its lack of backbone and the ability to breathe in water. 

Prawns and fishes are both water based animals. With the exception of similar living environments and fins on their bodies, both fish and prawns are completely different from each other. This article helps in highlighting the difference between the two sea animals.

Prawns, also called as shrimp, are large swimming crustaceans, found on the ocean floor in search for food. Usually, prawns are referred to as decapod crustaceans that are found in salt water as well as fresh water. The term ‘decapod crustaceans’ refers to creatures having an exoskeleton and 10 legs, which means that prawns have exoskeleton, from which they molt and grow.

Fish, on the other hand, is a member of a paraphyletic group, which consists of all gill-bearing aquatic animals. It is classified on the basis of cartilaginous and bony groups. They are ‘ectothermic’ in nature and can be abundantly found in all water bodies such as high mountain streams, abyssals and the deepest oceans. Although, prawns are said to be found in water, they are not categorized as fishes, because fishes are not a proper grouping, as it excludes all the amphibians, reptiles, birds and mammals from its category.

In terms of size and height, both fish and prawns are more or less the same, however, in terms of their structure and bodies, both are totally different. Prawns have a shell covering over their bodies, and are made up of 19 body segments, which are divided into two main body parts: the cephalothorax and the pleon (abdomen). On the other hand, fishes have fins on their bodies and scales on their skin. They breathe through their gills and are cold-blooded in nature. Along with that, fishes also have backbones, whereas prawns lack spines.

Fishes are known as vertebrates, whereas prawns are known as invertebrates. For respiration, prawns use branching gills, while fishes respire through covered gill slits. Both, fish and prawns are widely used for cooking in many countries around the world, also they are an individual part of the diverse delicacies. Also, both are prepared and cooked differently. Fish are often grilled or pan grilled, whereas prawns are sauteed, fried, grilled, etc. Also, there are different types of fish, such as salmon, tuna, etc, while there are tiger prawns, jumbo prawns, etc.

Thus, based on the above explanation, it can be said that prawns are not fishes. Also, further differences between the two can be read in the table below.

Comparison between Fish and Prawn:

Image Courtesy: theguardian.com, normalaquatics.com