Discoaster brouweri Tan Sin Hok, 1927
Eu-discoaster Tan Sin Hok, 1927
Helio-discoaster Tan Sin Hok, 1927
Hemi-discoaster, Tan Sin Hok, 1927
Asterolithes Sujowski, 1931
Gyrodiscoaster Stradner, 1961
Agalmatoaster (Gemminiodicoaster) Prins, 1971
Radiodiscoaster (Curvidiscoaster) Prins, 1971
Truncodiscoaster Prins, 1971
Turbodiscoaster Prins, 1971
Stellate, rosette shape or discoidal nannolith often concave-convex.
The segments are non-birefringent in plan view.
The inner end of the segments may form distal and proximal processes.
The segments entirely or partly join each other.
The termination of segments can be simple, bifurcated or twisted.
The ridges and depression or other ornamentations may be present on the segments.
The two major groups can be identified [each group can be further subdivided]:
Rosette-shaped discoasters, having segments joined each other almost entirely their length.
Stellate discoasters, having segments only partly joined each other, leaving a distinct free length of segments.
The species of Discoaster are identified based on the following main criteria:
The number of segments, length of the segment, termination of segments and the presence or absence of nodes.
The diameter of the central area, the central area ornamentation
The ratio of the central area to free length of segments.
The shape of inter-segments areas.
Prins, B., (1971): Speculations on relations, evolution and stratigraphic distribution of discoasters. In, Farinacci, A. (ed.) - Proceedings of the Second Planktonic Conference Roma 1970. Edizioni Tecnoscienza, Rome 2: 1017-1037.
Stradner, H., (1961): Vorkommen von Nannofossilien im Mesozoikum und Alttertiär. - Erdoel-Zeitschrift. 77(3): 77-88.
Sujkowski, Z., (1931): Étude pétrographique de Crétacé de Pologne. - Sprawozdania Polskiego instytutu geologicznego. 6: 485-628.
Tan Sin Hok, (1927): Discoasteridae incertae sedis. - Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen. Sect Sci, 30: 411-419.