Microgamete formation and the growth rate of Tintinnopsis beroidea

Microgametes have been detected for a species of Tintinnida for the first time. Apparently this method of sexual reproduction occurs rather infrequently in nature, whereas it is the predominant sexual process in vitro. Culturing conditions and the maintenance medium undoubtedly have a profound influence on microgamete appearance. The rate of division of Tintinnopsis beroidea is related to the degree of sexuality of the cells. Newly isolated cells have a doubling time of 0.8 to 1.1 day at an optimum ratio of food: protozoa. The new cultures have a low incidence of microgamete production.This work was supported by a contract with the U.S. Atomic Energy Commission, reference number NYO-3658-29.