King prawn

Prawn is a common name for small aquatic crustaceans with an exoskeleton and ten legs (i.e. a member of the order decapoda), some of which can be eaten.

The term "prawn" is used particularly in the United Kingdom, Ireland, and Commonwealth nations, for large swimming crustaceans or shrimp, especially those with commercial significance in the fishing industry. Shrimp that fall in this category often belong to the suborder Dendrobranchiata. In North America, the term is used less frequently, typically for freshwater shrimp. The terms shrimp and prawn themselves lack scientific standing. Over the years, the way shrimp and prawn are used has changed, and nowadays the terms are almost interchangeable.

In the United Kingdom, prawn is more common on menus than shrimp, while the opposite is the case in the United States. The term prawn also loosely describes any large shrimp, especially those at 15 (or fewer) to the pound (such as king prawns or jumbo shrimp).

The terms shrimp and prawn are common names, not scientific names. They are vernacular or colloquial terms which lack the formal definition of scientific terms. They are not taxa, but are terms of convenience with little circumscriptional significance. There is no reason to avoid using the terms shrimp or prawn when convenient, but it is important not to confuse them with the names or relationships of actual taxa.

According to the crustacean taxonomist Tin-Yam Chan, "The terms shrimp and prawn have no definite reference to any known taxonomic groups. Although the term shrimp is sometimes applied to smaller species, while prawn is more often used for larger forms, there is no clear distinction between both terms and their usage is often confused or even reverse in different countries or regions." Writing in 1980, L. B. Holthuis noted that the terms prawn and shrimp were used inconsistently "even within a single region", generalising that larger species fished commercially were generally called shrimps in the United States, and prawns in other English-speaking countries, although not without exceptions.

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