Invasion History

First Non-native North American Tidal Record: 1993
First Non-native West Coast Tidal Record: 1993
First Non-native East/Gulf Coast Tidal Record:

General Invasion History:

Palaemon carinicauda is a shrimp of estuarine and coastal marine waters, from the Bohai and Yellow Seas, China, to Singapore (Holthuis 1980; Wicksten 1997; Guo et al. 2005).

North American Invasion History:

Invasion History on the West Coast:

In 1993, one specimen of P. carinicauda was caught by an angler off Dumbarton Point in South San Francisco Bay. In 1995, a second specimen was trawled by the California Department of Fish and Game near Dumbarton Bridge (Wicksten 1997). We know of no further records of this Asian shrimp in US waters. Possible vectors are ballast water or the release of live shrimp purchased as seafood (Wicksten 1997).


Palaemon carinicauda is a caridean shrimp. Infraorder characteristics include chelae (movable claws) on the first two pairs of walking legs, and a third thoracic segment overlapping the second. This shrimp has a translucent body, a long toothed rostrum and large chelae on the 2nd perieopods (walking legs). The rostrum is as long as or shorter than the carapace. The elevated basal crest of the rostrum is longer than the slender distal part. The carpus (wrist) of the second pereiopod is shorter than the chela (claw). The rostrum is unarmed on the anterior half of the dorsal margin. The eggs measure 0.50-0.70 x 0.70-0.90 mm (Emmett et al. 2002; Guo et al. 2005). Palaemon carinicauda can be distinguished from P. modestus by the larger chelae (claws) of the second pereiopod in P. modestus. Also P. carinicauda has small setae which do not go beyond the median telson (tail) process, while P. modestus has two distal spines projecting beyond the tip of the median telson process (Kubo 1942, cited by Emmett et al. 2002).

A recent revision of the genus Palaemon and its relatives has moved the shrimps of the genus Exopalaemon back into the genus Palaemon (de Grave and Ashelby 2013).


Taxonomic Tree

Kingdom:   Animalia
Phylum:   Arthropoda
Subphylum:   Crustacea
Class:   Malacostraca
Subclass:   Eumalacostraca
Superorder:   Eucarida
Order:   Decapoda
Suborder:   Pleocyemata
Infraorder:   Caridea
Family:   Palaemonidae
Genus:   Palaemon
Species:   carinicauda


Leander longirostris carinicauda (Holthuis, 1950)
Exopalaemon carinicauda (Holthuis, 1950)
Palaemon carinicauda (de Grave and Ashelby, 2013)

Potentially Misidentified Species

Palaemon macrodactylus

Palaemon modestus



Life History- In caridean shrimps, the copulating pair is usually oriented at right angles to one another, with the genital regions opposing each other. The modified first and second pairs of pleopods are used to transfer a spermatophore to a receptacle between the thoracic legs of the female (Barnes 1983). After mating, female palaemonid shrimps carry broods of fertilized eggs on their abdomen. These hatch into planktonic larvae with feathery appendages, called zoeae. Zoeae of shrimps lack the prominent spines seen in brachyuran crabs, and look quite shrimplike (Johnson and Allen 2005). They go through several molts and metamorphose into postlarvae, which have well-developed walking legs and pleopods (swimmerets). After a subsequent molt, the body takes on the adult shape.

Ecology- Palaemon carinicauda is a widespread species of estuarine and coastal marine waters from China to Singapore (Holthuis 1980; Wicksten 1997; Guo et al. 2005).

Trophic Status:




General HabitatUnstructured BottomNone
General HabitatGrass BedNone
General HabitatSalt-brackish marshNone
General HabitatMangrovesNone
Salinity RangeMesohaline5-18 PSU
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Vertical HabitatEpibenthicNone
Vertical HabitatNektonicNone

Tolerances and Life History Parameters

Minimum Temperature (ºC)7Lowest tested (Xingqiang et al. 2010)
Minimum Salinity (‰)0.2Xingqiang et al. 2010
Maximum Length (mm)97Holthuis 1980
Broad Temperature RangeNoneCold temperate-Tropical
Broad Salinity RangeNoneOligohaline-Euhaline

General Impacts

Palaemon carinicauda is well-regarded as seafood (Holthuis 1980; Wicksten 1997) and is raised in aquaculture in China (Guo et al. 2005). Imports of this shrimp to the United States and elsewhere are likely, however, we know of no other invasions or impacts.

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
NWP-3a None 0 Native Estab
P090 San Francisco Bay 1993 Def Unk
NWP-2 None 0 Native Estab
NWP-4a None 0 Native Estab
NEP-V Northern California to Mid Channel Islands 1993 Def Unk
EAS-I None 0 Native Estab

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude


Barnes, Robert D. (1983) Invertebrate Zoology, Saunders, Philadelphia. Pp. 883

de Grave, Sammy; Ashelby, Christopher W. (2013) A re-appraisal of the systematic status of selected genera in Palaemoninae (Crustacea: Decapoda: Palaemonidae), Zootaxa 3734(3): 331-344

Emmett, Robert L; Hinton, Susan A; Logan, Dan (2002) Introduction of a Siberian freshwater shrimp to western North America., Biological Invasions 4: 447-450

Guo, Zhao Liang; Wang, Xiao Qing; Zhang, Ji Ping (2005) On the genus Exopalaemon (Decapoda, Caridea, Palaemonidae) in Guangdong Province, southern China., Crustaceana 78(7): 839-850

Holthuis, L. B. (1980) FAO Species Catalogue: Vol. 1. Shrimps and Prawns of the World., Food and Agricultural Organization, Rome. Pp. <missing location>

Huang, Zongguo (Ed.), Junda Lin (Translator) (2001) Marine Species and Their Distributions in China's Seas, Krieger, Malabar, FL. Pp. <missing location>

Johnson, William S.; Allen, Dennis M. (2005) <missing title>, Johns Hopkins Press, Baltimore. Pp. <missing location>

Kuris, Armand; Sadeghian, Patricia S.; Carlton, James T. (2007) The Light and Smith Manual: Intertidal Invertebrates from Central California to Oregon, University of California Press, Berkeley CA. Pp. 636-656

Wicksten, Mary K. (1997) Introduction of the ridgetail prawn, Exopalaemon carinicauda, into San Francisco Bay, California, California Fish and Game 83(1): 43-44

Xingqiang, Wang; Sudha, Kappalli; Cao, Mei; Ma, Shen (2010) Effects of low salinity and low temperature on survival, growth, and energy budget of juvenile Exopalaemon carinicauda, Journal of Shellfish Research 29(4): 1035-1041