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Bostrichobranchus pilularis
Image courtesy of Christina Simkanin, redrawn from Van Name, 1945. Image shows the left and right sides of the body. 
Bostrichobranchus pilularis
Taxonomic Group: Tunicates


Bostrichobranchus pilularis is a solitary tunicate, which occurs unattached in soft sediments. Its body is globular, and often covered with short fibers which sand and mud adhere to. When its siphons are retracted, it can look like a small ball of mud. It is native to the Eastern and Gulf coasts of North America, ranging from the Gulf of St. Lawrence, Canada to the west coast of Florida and Texas. There is only one record of B. pilularis being introduced in North America, from San Dieguito Lagoon, in Southern California. This tunicate was not found in subsequent collections here or elsewhere, so we consider this a failed invasion. No ecological or economic impacts are known from this short-lived invasion.

*Outside of its native range, this species is not currently established in North American waters.

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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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