Taxonomy:
Distinguishing features:
Parent taxon (Markalius): Circular placoliths with moderately birefringent shields, bright inner tube cycle and narrow or closed central areas.
This taxon: Markalius with open central area.
Farinacci & Howe catalog pages: M. apertus *
Search data:
LITHS: placolith, circular, CA: vacant, CSPH: equant, monomorphic, CROSS-POLARS: V-prominent, R-prominent, rim-bicyclic, |
Lith size: 6->9µm; Liths per sphere: 12->16 Data source notes: lith size from illustrated specs |
Geological Range:
Last occurrence (top): within NP16 zone (40.40-42.87Ma, top in Bartonian stage). Data source: Neptune records, Self-Trail 2011
First occurrence (base): within NP1 zone (65.47-66.04Ma, base in Danian stage). Data source: Neptune records
Plot of occurrence data:
Bown, P. R., Gibbs, S. J., Sheward, R., O’Dea, S. & Higgins, D. (2014). Searching for cells: the potential of fossil coccospheres in coccolithophore research. Journal of Nannoplankton Research. 34(S): 5-21. gs 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. gs O Bramlette, M. N. & Martini, E. (1964). The great change in calcareous nannoplankton fossils between the Maestrichtian and Danian. Micropaleontology. 10(2): 291-322. gs Bybell, L. M. & Self-Trail, J. (1995). Evolutionary, biostratigraphic and taxonomic study of calcareous nanofossils from a continuous Palaeocene-Eocene boundary section in New Jersey. U.S. Geological Survey, Professional Paper. 1554: 1-36. gs O Okada, H. & Thierstein, H. R. (1979). Calcareous nannoplankton - Leg 43, Deep Sea Drilling Project. Initial Reports of the Deep Sea Drilling Project. 43: 507-573. gs O Perch-Nielsen, K. (1977). Albian to Pleistocene calcareous nannofossils from the Western South Atlantic, DSDP Leg 39. Initial Reports of the Deep Sea Drilling Project. 39: 699-823. gs O Perch-Nielsen, K. (1979). Calcareous nannofossil zonation at the Cretaceous/Tertiary boundary in Denmark. In, Birkelund, T. & Bromley, R. G. (eds) Proceedings Cretaceous-Tertiary Boundary Events Symposium, Copenhagen, 1. Copenhagen 115-135. gs O Pospichal, J. J. & Bralower, T. J. (1992). Calcareous Nannofossils Across the Cretaceous/Tertiary Boundary, Site 761, Northwest Australian Margin. Proceedings of the Ocean Drilling Program, Scientific Results. 122: 735-752. gs Pospichal, J. J. & Wise, S. W. (1990). Paleocene to Middle Eocene calcareous nannofossils of ODP sites 689 and 690, Maud Rise, Weddell Sea. Proceedings of the Ocean Drilling Program, Scientific Results. 113: 613-638. gs Self-Trail, J. (2011). Paleogene Calcareous Nannofossils of the South Dover Bridge core, Southern Maryland (USA). Journal of Nannoplankton Research. 32(1): 1-28. gs Self-Trail, J. M., Powars, D. S., Watkins, D. K. & Wandless, G. A. (2012). Calcareous nannofossil assemblage changes across the Paleocene–Eocene Thermal Maximum: Evidence from a shelf setting. Marine Micropaleontology. 92–93: 61-80. gs Self-Trail, J. M., Parker, M., Govoni, D. L., Bybell, L. M., Gardner, K. F. & Gohn, G. S. (2023). Designation of a composite-stratotype section for the lower Paleocene (Danian) Brightseat Formation in Prince George’s County, Maryland, USA. Stratigraphy. 20(4): 237-258. gs Shepherd, C. L. & Kulhanek, D. K. (2016). Eocene nannofossil biostratigraphy of the mid-Waipara River section, Canterbury Basin, New Zealand. Journal of Nannoplankton Research. 36(1): 33-59. gs O Thibault, N. (2010). Calcareous nannofossils from the boreal Upper Campanian- Maastrichtian chalk of Denmark. Journal of Nannoplankton Research. 31(1): 39-56. gs Varol, O. (1998). Palaeogene. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series . 200-224. gs References:
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Markalius apertus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 14-2-2025
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=839 Go to Archive.is to create a permanent copy of this page - citation notes |
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