Growth of the spinose planktonic foraminifer Orbulina universa in laboratory culture and the effect of temperature on life processes

Abstract
Orbulina universa d'Orbigny is a spinose planktonic foraminifer which occurs throughout surface waters of the tropical, subtropical and transition zones of the world ocean (Bé & Tolderlund, 1971). This species is unique among planktonic Foraminifera in that its life cycle is composed of two growth stages. The juvenile stage is a trochospiral form which is enclosed within a terminal spherical chamber in the adult stage. O. universa is relatively omnivorous, and consumes a variety of prey that range in size and quality from phytoplankton to copepods (Bé et al. 1977; Anderson et al. 1979; Spindler et al. 1984). In addition, each individual harbors several thousand zooxanthellae which presumably are an additional source of nutrition for the foraminifer (Be et al. 1977; Hemleben & Spindler, 1983; Spero & Parker, 1985).