Type Genus

Polycyclolithus Forchheimer, 1968


Lithastrinaceae Thierstein, 1973

Eprolithaceae Black, 1973


Nannoliths have two vertical wall cycles and a central area that may be closed, vacant, or spanned by a left-handed imbricated diaphragm. Segments have tangential c-axis orientation.


Black, M., 1973. British Lower Cretaceous Coccoliths. I-Gault Clay (Part 2). Palaeontographical Society Monograph 127, 49-112.

Forchheimer, S., 1972. Scanning electron microscope studies of Cretaceous coccoliths from the Köpingsberg Borehole No. 1, SE Sweden. Sveriges Geologiska Undersökning, Series C. #668, 65, 1-141.

Thierstein, H. R., 1973. Lower cretaceous calcareous nannoplankton biostratigraphy. Abhandlungen der Geologischen Bundesanstalt. 29, 3-52.