Abstracted/indexed

This study presents a taxonomic revision of calcareous nannoplankton, known as fasciculiths (family Fasciculithaceae). The investigation approach is based on a direct light microscope and SEM comparison of the same individual specimen, providing a key to clarify a correct classification of several taxa. The new findings document the early evolutionary history of fasciculiths, demonstrating the biostratigraphic relevance of this group in the early Paleocene (Danian–Selandian transition).

Coccolithophores are an important group of phytoplankton that produce intricate skeletons of calcium carbonate. They contribute to the base of the marine food web and are important drivers of the global carbon cycle. Here, we describe novel coccolithophores and novel life cycle combinations detected by electron microscopy in samples collected in the Red Sea and the western Mediterranean. Our study advances our understanding of coccolithophore diversity and life cycle complexity.

The study presents (1) a validation of a method which was previously published allowing us to recognize different Ammonia phylotypes (T1, T2 and T6) based only on their morphology and (2) a refined biogeographical distribution presented here supporting the putatively invasive character of phylotype T6. Results suggest that phylotype T6 is currently spreading out and supplanting autochthonous phylotypes T1 and T2 along the coastlines of the British Isles and northern France.