About the Data
Species records include data on invasions history, distribution, ecology, impact, and more. These data were gathered from published literature and targeted surveys. All records have undergone expert review, unless otherwise noted.
Species Profiles
NEMESIS includes detailed information on about 500 species of marine and estuarine of invertebrates and algae introduced to the United States. Each record contains information on taxonomy, distribution, ecology, and impacts, as well as references.
Daily Invader

Bostrichobranchus pilularis
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.
Daily Invader for 2023-09-17