It's true that prawns and shrimp are very similar in appearance, taste, and uses, but they are not the same critter--in fact they are completely different species.
Shrimp vs. Prawns?
Shrimp are among several thousand species in the suborder Pleocyemata (remember biology class?), while prawns fall under the suborder Dendrobranchiata, which also has several thousand species. The most obvious difference between them is that prawns are larger than shrimp, with prawns generally over four inches in length and shrimp smaller. But there is some overlap in size, so it is not a guaranteed way to tell.
Aside from size, how can you tell them apart, and is there any need to? Some people claim that there are subtle differences in taste and texture, with prawns tending to be sweeter and meatier. Of course, the larger size of prawns is prized, so prawns tend to be more expensive than shrimp. So, if a restaurant serves you pricey "prawns" that are much under four inches, maybe raise an eyebrow!
How to Tell Prawns From Shrimp
Once they have been cooked, there is no way to tell shrimp and prawns apart other than size—and as I mentioned above, size is not always reliable. When raw, however, there are some differences. Prawns tend to have straighter bodies than shrimp, which are more curved. Shrimp possess claws on two of their five pairs of legs, whereas prawns have claws on three pairs of legs. Additionally, prawns have larger pincers on the second pair of legs.
Whether prawns or shrimp, I'll have a double order!
