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Fleshy prawns being sold at Noryangjin Fish Market, South Korea
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Malacostraca
Order:	Decapoda
Suborder:	Dendrobranchiata
Family:	Penaeidae
Genus:	Fenneropenaeus
Species:	F. chinensis
Binomial name
Fenneropenaeus chinensis (Osbeck, 1765)
Synonyms
Cancer chinensis Osbeck, 1765 Penaeus chinensis (Osbeck, 1765) Penaeus orientalis Kishinouye, 1917

The Chinese white shrimp, oriental shrimp, or fleshy prawn (Fenneropenaeus chinensis) is a species of shrimp. It is cultivated at an industrial level off mainland China. Production was devastated by a series of epidemics in the 1990s and early 2000s. Its wild capture has since recovered and expanded, but it is now farmed at lower levels than previously.

It was formerly known as Cancer chinensis, Penaeus chinensis and Penaeus orientalis, but has been reassigned to Fenneropenaeus.

Anatomy and Morphology

Penaeidae shrimp such as F. chinensis are laterally compressed and elongated, typical for a member of the class Malacostraca. Males may reach a total length of 154 mm and females a total length of 183 mm. They are composed of thirteen segments, called somites. Five somites make up the head and are fused with the eight segments of the thorax. The carapace, an especially thick shell, completely covers the head. A rostrum, a rigid horn-like structure, protrudes from the head and can be used in attack or defense. A pair of compound eyes sit on adjustable stalks below the rostrum. The species has one pair of shorter antennae called antennules and one pair of antennae with greatly elongated flagella which may be as long as, or longer, than their body. These flagella may be used as a rudder to quickly escape from predators. Their mandibles are long, curved, and made of hard sclerotin which makes them capable of catching and grinding prey such as mollusks. Two pairs of appendages, maxillae, aid in processing food and pumping water over the gills. The thoracic appendages include three pairs of maxillipeds and five pairs of pleopods, or walking legs. A pair of paddle-shaped uropods, paddle-like appendages, are connected to the sixth abdominal segment as well as the spiny structure called the telson. Together they comprise the tail fin.

Anatomy of the general Penaeid shrimp body plan.

Distribution

This species is trawled mainly in the Yellow Sea, East China Sea and Korean Bight of the Western Pacific Ocean. However, it has been observed off the coast of North Korea in the Sea of Japan and southwest along China's entire coast. They are found in waters ranging from a depth of 90 to 180 m and temperatures between 18 and 28°C.

Life Stages and Reproduction

F. chinensis exhibits typical penaeid behavior in that it migrates between sea water and brackish water depending on its life stage. Mating occurs in sea water once the shrimps reach sexual maturity. F. chinensis have a closed theylacum which means their cuticle covers the modified region on the females's sternum used for reproduction. Therefore males must implant their spermatophores, sacks of spermatozoa, into the females after they molt. They use their first pair of tetrapods, which are specially modified into a structure called a petasma, for sperm transfer. Spawning happens before their next molt when females release both eggs and sperm. After fertilization, the eggs take about fourteen hours to hatch and begin to develop through a process of molting. They begin as an unsegmented nautilus larva which feeds on yolk then go through a series of four molts before becoming a protozoea after the fifth molt. At this point the shrimp have become segmented, have stalked eyes, and uripods. They continue to molt and develop into a mysis then a post-larval stage and finally into a postlarval shrimp. After spawning and developing into a juvenile state they may then be carried into brackish water by currents before returning again to the sea to reach sexual maturity and spawn.

Taxonomy

Penaeid shrimp posses jointed appendages and a rigid cuticle which restricts growth and must be shed periodically. These are characteristics of the largest phylum in the animal kingdom, Arthropoda.They are placed into the superorder Eucarida because they go through indirect development in which the larva must grow through a series of larval stages before attaining their adult body plan. This species has ten segmented legs which aid in distinguishing them from other Crustaceans, and the function and structure of the appendages places them into the Order Decapoda meaning "ten-legs." F. chinensis is commonly mistaken for F. indicus, the Indian white Prawn, due to their similar appearance.

Conservation Status

A very small percent of naturally spawned shrimp are predicted to reach adulthood and their susceptibility to disease put the commercially valuable species at risk. In 1984, in response to the decimation of the species due to disease and overfishing, China began releasing juvenile F. chinensis in an effort to increase the corresponding annual catch. The program produced considerable results, with an average release of approximately 600 million and catch of 720 tons annually as of 2006. Due to the species' commercial value extensive research is available regarding diet and optimal growth conditions.