Helicopontosphaera sellii Bukry and Bramlette,1969
Helicolith having a Type III (Helicosphaera carteri type) blanket, expanded flange termination and a central area with a moderate size central opening spanned by a conjunct traverse bar.
Helicosphaera sellii differs from Helicosphaera carteri (Wallich, 1877) Kamptner (1954) and Helicosphaera bownii da Gama & Varol (2013) by having a larger central opening. It is further distinguished from Helicosphaera bownii by its younger stratigraphic occurrence.
Bukry, D. & Bramlette, M. N., (1969): Some new and stratigraphically useful calcareous nannofossils of the Cenozoic. - Tulane Studies in Geology. 7: 131-142.
da Gama, R. O. B. P. & Varol, O., (2013): New Late Oligocene to Miocene Species. - Journal of Nannoplankton Research. 33(1): 1-12.
Jafar, S. A. & Martini, E., (1975): On the validity of the calcareous nannoplankton genus Helicosphaera. - Senckenbergiana Lethaea. 56: 381-397.
Wallich, G. C., (1877): Observations on the coccosphere. - Annals and Magazine of Natural History. 19: 342-350.
Helicopontosphaera sellii (Bukry & Bramlette, 1969)
Jafar & Martini, 1965
Le Castella 81, Calabria, Italy