Type species. Calyptooecia insidiosa Winston, 1984, by original designation.
Diagnosis (amended). Colony encrusting, multilaminar. Zooids erect, roughly hexagonal, the frontal skeletal surface perforated by rounded to cruciform pores. Orificial anter high-arched, with broad shallow poster delimited from anter by stout condyles. No ovicells; embryos brooded in dimorphic female zooids with smaller orifices and less frontal area than non-brooding zooids.
Remarks. Calyptooecia was erected by Winston (1984) to accommodate only the type species, C. insidiosa, upon which the generic characters were necessarily exclusively based. The discovery of the new species reported here has necessitated amending the generic diagnosis slightly to accommodate non-cruciform frontal-shield pores. Winston (1984) noted that the apparent zooidal dimorphism was somewhat equivocal owing the varying degrees of zooidal calcification. Here, we confirm zooidal dimorphism, which is pronounced in Calyptooecia conuma n. sp. Both species form hemispherical to mushroom-shaped mounds on different substrata.