Heliolithales
Columnar nannofossils consist of a column and one or two discs, which may or may not be birefringent, as in Family Heliolithaceae Hay and Mohler (1967), or having a column with or without a cone (calyptra and collaret), as in Fasciculithaceae Hay and Mohler (1967). Vertically arranged pillar-like segments form the column , which is birefringent in plan and side views.
The families of this Order have been traditionally assigned to the planar asterolith Discoasterales Hok (1927) (non-birefringent stellate or rosette shape nannofossils in plan view).
Family Fasciculithaceae Hay and Mohler (1967).
- Genus Diantholitha Aubry in Aubry et al. (2011).
- Genus Fasciculithus Bramlette and Sullivan (1961).
- Genus Gomphiolithus Aubry in Aubry et al. (2011).
- Genus Lithoptychius Aubry in Aubry et al. (2011).
Family Heliolithaceae Hay and Mohler (1967).
- Genus Asinithistimorfi Bowman and Varol, gen. nov.
- Genus Bomolithus Roth (1973).
- Genus Caycedoa Bowman and Varol, gen. nov.
- Genus Heliolithus Bramlette and Sullivan (1961).
- Genus Heliotrochus Aubry (2014).
- Genus Tonromeinia Bowman and Varol, gen. nov.
Aubry, M. -P. 2015. Cenozoic Coccolithophores: Discoasterales. Micropaleontology Press, American Museum of Natural History, New York. pp. 1-455.
Aubry, M. P., Bord, D. & Rodriguez, O. 2011. New taxa of the Order Discoasterales Hay 1977. Micropaleontology. 57(3): 269-287.
Bowman, A. R. & Varol, O. 2021. A Taxonomic Revision of Heliolithaceae - Applications in Resolving the Problematic Calcareous Nannofossil Biostratigraphy of the Paleocene. In: M. Montenary, M. (Ed.). Calcareous nannofossil biostratigraphy of the Stratigraphy and timescales. 6: 43-223.
Bramlette, M. N. & Sullivan, F. R. 1961, Coccolithophorids and related nannoplankton of the Early Tertiary in California. Micropaleontology 7(2): 129-188.
Hay, W. W. & Mohler, H. P. 1967, Calcareous nannoplankton from Early Tertiary rocks at Point Labau, France and Paleocene-Early Eocene correlations. Journal of Paleontology 41(6): 1505-1541.
Roth, P. H. 1973. Calcareous nannofossils: Leg 17 of the Deep Sea Drilling Project. Initial Reports of the Deep Sea Drilling Project. 17: 695-795.
