- according to Hottinger (2006):
COSTELLAE - a particular ornament on the chamber wall produced by more or less elongate ridges formed by an aligned fusion of pustules produced by secondary lamellation.
Remarks: The term was introduced to describe the particular ornament of Costellagerina, a rugoglobigerinid from the late Cretaceous. It might be useful to extend the term as a description of the radial ornamentation of the ventral chamber walls in smaller benthics indicating ogamy (pairing of two gamonts venter against venter), as in Glabratellina.
Hottinger (2006), Illustrated glossary of terms used in foraminiferal research. Carnets de Géologie, Memoir 2, ISSN 1634-0744