d'Orbigny, 1839
Easy to distinguish by last chamber: sphere encompassing weakly calcified small trochospire which is mostly resorbed during gametogenesis. Spines round and triangular. Adults feed mainly on calanoid copepods and other animal prey. With dinoflagellate symbionts.
Ref.: Bé et al. (1973), Vilks and Walker (1974), Weiner (1975), Caron et al. (1987b).
Distribution: In the South Atlantic this species seems to be almost restricted to warm water masses and upwelling areas of the Benguela front, with only a few specimens having been observed in cooler waters in the western South Atlantic (Boltovskoy, 1962). However, in the North Atlantic it ranges from subpolar/temperate regions to the tropics.