The genus SphaerodinellaKeupp and Versteegh, 1989, became obsolete by the assignment of its type S. albatrosiana (Kamptner, 1963) to the genus CalciodinellumDeflandre, 1947. For the single remaining species of Sphaerodinella, which does not fit into the genus Calciodinellum, the new genus Caracomia is proposed, whose type is C. arctica (Gilbert and Clark, 1983) new genus, new combination. Additionally, a new species of Caracomia is described: Caracomia stella new genus and species. The regional distribution of the two species of Caracomia shows distinct regional preferences: Caracomia arctica is restricted to cold waters of both hemispheres, whereas Caracomia stella as yet has only been described from warmer environments. Thus, C. arctica can be used as a cold water indicator. Comparison of Caracomia with other genera has shown a close relationship to the type of Orthopithonella and exposed a common misinterpretation of this genus. Therefore, the genus Orthopithonella Keupp inKeupp and Mutterlose, 1984, is emended to unquestionably accommodate only the type O. gustafsonii.