Papposphaera obpyramidalis (Haptophyta, Papposphaeraceae): New findings from both Polar Regions

Papposphaera obpyramidalis is reinvestigated based on additional high latitude sampling from the southern hemisphere. The material used here comprises better preserved transmission electron microscope (TEM) material including several cells with complete flagellation, as well as light microscopy (LM) of living material. The re-examination basically confirms the findings that were part of the species description but also adds details on, for example, nutritional mode and the presence of an underlayer of unmineralized scales. P. obpyramidalis has hitherto been considered confined to Antarctic waters. However, here we present also findings of the species from Arctic realms based on recent SEM surveys from the Svalbard region, indicating a bipolar distribution.