Braarudosphaera pentagonica n.sp., a new Braarudosphaera from the lowermost Tertiary of Geulhemmerberg (Geulhem, The Netherlands)

摘要

From the lowermost Danian, Biantholithus sparsus zone, the new calcareous nannofossil species Braarudosphaera pentagonica n.sp. is described. It is composed of 12 pentaliths, each built of five segments with a pentagonal outline. All sutures between the pentaliths are zigzag shaped. Proximal and distal faces (plate 2, figs. 3, 4) are of the same pentalith, illustriations obtained by the new "turn over technique" introduced by Mai 1995.