Praeprinsius dimorphosus

Biscutum dimorphosum Perch-Nielsen, 1969a

The holotype is 3.5µm long.

An elliptical species of Praeprinsius exhibiting a distinctly closed central area.

The holotype is represented by a SEM micrograph of a coccosphere displaying a single tube cycle. The specimens with a double-tube cycle were erroneously included in this species (i.e., Bown et al., 2023), thereby contributing to taxonomic ambiguity. The specimens with a double-tube cycle, if less than 3.0µm, are assigned to Prinsius taganus, but if more than 3.0µm, they are assigned to Prinsius martinii here.

This species often constitutes the dominant component of assemblages from 65.59 Ma to 62.10 Ma.

Bown, P. R., Kim, H. & Gibbs, S. J. 2023. Danian calcareous nannofossil evolution and taxonomy with focus on sites from the North Atlantic Ocean (IODP Expedition 342, Sites U1403 and U1407). Journal of Nannoplankton Research. 41(2): 110-157

Fonseca, B. 1976. Coccolithus taganus, nouvelle espece de Coccolithopohride du Miocene de Lisbonne. Boletim de Sociedade Geologica de Portugal 20: 29-32.

Perch-Nielsen, K., 1969a. Die Coccolithen einiger danischer Maastrichtien- und Danienlokalitaten. Meddelelser fra Dansk Geologisk Forening 19, 51-68.

Varol, O. & Jakubowski, M. (1989). Some new nannofossil taxa. INA Newsletter. 11(1): 24-29.