Lithastrinus floralis Stradner, 1962
Polycyclolithus Forchheimer, 1968
Polycyclolith is characterised by a double-storey wall of equal height, with each wall comprising five to nine petal-like segments and a median diaphragm spanning the central opening. The distinctions among related genera—Eprolithus, Lithastrinus, Quadrum, Radiolithus, and Farhania—are based on the presence and size of the diaphragm and the shape and arrangement of the wall segments.
A wide diaphragm distinguishes Eprolithus, while Lithastrinus has a very narrow diaphragm, and Quadrum lacks one entirely. Radiolithus and Farhania differ from Eprolithus because they possess amedian diaphragms and brick-like wall segments.
Forchheimer, S. 1968. Die Coccolithen des Gault-Cenoman, Cenoman und Turon in der Bohrung Höllviken I, Süd-west-Schweden. Sveriges Geologiska Undersökning, Series C. #635: 62(6), 1-64.
Stover, L. E. 1966. Cretaceous coccoliths and associated nannofossils from France and the Netherlands. Micropaleontology 12(2): 133-167.
Stradner, H. 1962. Über neue und wenig bekannte Nannofossilien aus Kreide und Alttertiär. Verhandlungen der Geologischen Bundesanstalt (Wien) 2: 363-377.