New and intriguing calcareous nannofossils from the Turonian (Upper Cretaceous) of Tanzania.

Abstract

The preservation of exceptionally well-preserved, primary associations of calcareous nannofossils on lamina surfaces of shallowly-buried, uncemented, clay-rich Turonian sediments of coastal Tanzania has enabled us to document several intriguing new morphologies using the scanning electron microscope (SEM). Based on our new observations, we describe a new genus, Jimenezberrocosoia, and six new species, J. birchiae, Ellipsolithus linnertii, Petrarhabdus? kirenii, Braarudosphaera wendleriae, Nannoconus funiculus and Kokia kayae. We have also made two new combinations, Jimenezberrocosoia bosunensis (Jeremiah, 2001) and Nannoconus nicholasii (Lees, 2007), and emended the Order Braarudosphaerales to include the Nannoconaceae. Most of the taxa are illustrated with both SEM and light microscope images.The presence of Ellipsolithus in these Cretaceous sediments greatly extends the range of this formerly Cenozoic-restricted taxon.