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Tortanus dextrilobatus
Image courtesy of Tricia Bippus, California Department of Fish and Wildlife, IEP Diet and Condition Study. Please note that the specimen has been stained with Rose Bengal dye
Tortanus dextrilobatus
Taxonomic Group: Crustaceans-Copepods


Tortanus dextrilobatus is a calanoid copepod which is native to Asia from South Korea to China. It has been introduced to San Francisco Bay, California, but no other non-native locations are known. It is characteristic of low-salinity coastal waters and can tolerate salinities from 1-28 PSU. It has been reported in ballast water aboard commercial vessels arriving to Puget Sound, Washington, which is the likely invasion vector for this species. It is a predatory copepod, feeding on smaller copepod species. It has had a significant impact on zooplankton in San Francisco Bay, through predation, but its full impact on the food web requires more study.

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Fofonoff PW, Ruiz GM, Steves B, Simkanin C, & Carlton JT (2018)
National Exotic Marine and Estuarine Species Information System.
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Marine Invasions Lab
Smithsonian Environmental Research Center

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