Calcidiscus tanianus

Cyclococcolithus tanianus Kamptner 1955

Moderately large [6.0 - 10.0µm] circular species of Calcidiscus having a narrow central opening surrounded by a birefringent wide tube cycle. The central area is without structure. The proximal shield is smaller than the distal shield and birefringent.

Calcidiscus tanianus differs from Calcidiscus leptoporus (Murray & Blackman 1898) Loeblich & Tappan (1978) by having an open central opening. It is distinguished from Calcidiscus tropicus (Kamptner, 1955) Varol (1989) by being smaller than 10.0µm, whereas the latter is greater than 10.0µm.

da Gama, R. O. B. P. & Varol, O., (2013): New Late Oligocene to Miocene Species. - Journal of Nannoplankton Research. 33(1): 1-12.

Kamptner, E., (1955): Fossile Coccolithineen-Skelettreste aus Insulinde. Eine mikropaläontologische Untersuchung. - Verhandelingen der Koninklijke Nederlandse Akademie van Wetenschappen, Afdeling Natuurkunde. ser 2, 50: 1-105.

Loeblich, A. R. & Tappan, H., (1978): The coccolithophorid genus Calcidiscus Kamptner and its synonyms. - Journal of Paleontology. 52: 1390-1392.

Murray, G. & Blackman, V. H., (1898): On the nature of the Coccospheres and Rhabdospheres. - Philosophical Transactions of the Royal Society of London B: Biological Sciences. 190(1): 427-441.

Varol, O., (1989): Calcareous nannofossil study of the central and western Solomon Islands. - Circum-Pacific Council for Energy and Mineral Resources Earth Sciences. 239-268.