- according to Hottinger (2006):
CUBICULUM - (pl. cubicula); a lateral shell cavitiy in spiral and annular-concentric shells with a main chamber- or chamberlet- layer.
Remarks: This term, introduced by Banner and Hodgkinson (1991) and exemplified by Spiroclypeus, "orbitoid, miogypsine and other, three-layered rotalines" is a substitute for what is traditionally called lateral chamberlets in larger foraminifera (compare Ferrandez, 1999). Apparently, Banner and Hodgkinson mean by "true" lateral chamberlets in heterosteginids their alar prolongations subdivided into chamberlets. They show them only in axial or transverse sections where the distinction between septal and secondary subdivision of shell cavitiesis is difficult to carry out. I suspect these "lateral chamberlet" to be undivided alar prolongations cut at an oblique angle in respect to the median line of the alae.
Hottinger (2006), Illustrated glossary of terms used in foraminiferal research. Carnets de Géologie, Memoir 2, ISSN 1634-0744