The adults have a

Larvaceans, also known as "appendicularians" are small holoplanktonic animals with a very specialized holoplanktonic lifestyle. They secrete a hollow mucous "house" around themselves and use their tail (on the right) to create a current through the house that provides propulsion. A series of mucous filters strain micro-organisms from this current to feed the larvacean.

The houses are replaced periodically and are quickly jetisoned if the animal is disturbed, as invariably occurs when they are captured in plankton nets, The animal shown here is less than 0.5 mm long, but the house may reach several milimeters.

Oikopleura is the most common nearshore larvacean, usually found in clear, high-salinity waters. This specimen was caught well offshore, but they are occasionally caught very nearshore or even in high salinity bays.

lCollected by: Bill Johnson, Goucher College.