Laboratory culture of marine planktonic oligotrichs (Ciliophora, Oligotrichida)

Marine planktonic oligotrichs of the genera Strombidium and Strombidinopsis were collected from the Northwest Arm of Halifax Harbour, isolated, and maintained in monospecific batch culture for periods ranging from weeks to 10 mo. Successful laboratory culture was a function of appropriate phytoplankton food and the chemical composition of the oligotrich culture medium. Maximal reproductive rates, as doublings per day, were obtained when the oligotrichs were fed 2 dinoflagellate strains, Heterocapsa triquetra and Scrippsiella trochoidea, and when the organisms were grown in seawater medium containing 10-@ to 10-6 M Na,-EDTA and trace metals. Oligotrich cultures fed diatoms of the spinose genus Thalassiosira exhibited poor growth, regardless of the culture m e d ~u m used. Losses of oligotrichs from field collections due to handling ranged from 20 to 6 0 % , depending on the methods of collection and concentration used.