Articles | Volume 11, issue 1
01 Jun 1992
 | 01 Jun 1992

First record of the genus Beela Banner & Blow, 1960, in upper Pleistocene sediments (past 600Ka) from the Norwegian-Greenland Sea

Henning A. Bauch

Abstract. Planktonic foraminifers from Pleistocene sediments from the Norwegian-Greenland Sea (NGS) have been subject to intense investigation during the past 20 years. This is mainly due to their almost continuous presence in glacial and interglacial times, and hence, their utility for establishing sound O18-isotopic curves. Traditionally, all are assigned to a polar and subpolar group. Neogloboquadrina pachyderma (sinistral) is the only polar species, whereas the subpolar group is made up of Globigerina quinqueloba, G. bulloides, G. universa, N. pachyderma (dextral), N. dutertrei, Globigerinita glutinata, Gl. uvula, Globorotalia inflata, Glr. truncalutinoides, Glr. scitula. N. pachyderma (sinistral) is almost continuously present during glacial/interglacial times. This is in contrast to the subpolar species that show main abundances in interglacial maxima only. Prior to this study, a species belonging to the genus Beela has never been mentioned to occur in Pleistocene sediments north of 55° latitude (Holmes, 1984). My specimens exhibit a thin-walled spinose test; trochospiral becoming streptospiral; last chamber radially elongated but never pointed or digitate; aperture very variable from small umbilical to larger extraumbilical-umbilical. Its size ranges from 200–660μm, but is mainly confined to the 250–500μm mesh-size fraction.

These general characteristics agree well with the emendation of the genus Beela by Holmes (1984). Accordingly, the described species will in future be assigned to Beela megastoma (Earland).

There is good evidence that Beela megastoma is not simply a ‘warmer water form’ being swept into the NGS by North Atlantic Waters as some of those mentioned above, but a species that seems to. . .