Daughter taxa (time control age-window is: 0-800Ma)![]() | ||||
![]() | Octocyclus magnus Very large (>12 µm) | |||
Octocyclus reinhardtii Large (8-12 µm) | ||||
Octocyclus sp. Specimens not identified to species level |
Taxonomy:
Distinguishing features:
Parent taxon (Axopodorhabdaceae): Regular placoliths; central-area, with cross-bars or perforated plate; often with tall, hollow spines.
Distal shield elements non-imbricate V-units; proximal shield and inner cycle formed from R-units. Rim often appears beaded in LM
This taxon: Elliptical; central area spanned by eight bars delineating eight large perforations arranged either side of the long axis.
Farinacci & Howe catalog pages: Octocyclus *
Search data:
CA: placolith, ca_disjunct, grill, pores, process, CROSS-POLARS: rim-bicyclic, V-prominent, |
Lith size: 8->15µm; Data source notes: size range of included species |
Geological Range:
Last occurrence (top): at top of Maastrichtian Stage (100% up, 66Ma, in Danian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within Albian Stage (100.50-113.20Ma, base in Albian stage). Data source: Total of ranges of species in this database
Plot of occurrence data:
Black, M. (1972a). British Lower Cretaceous Coccoliths. I-Gault Clay (Part 1). Palaeontographical Society Monograph. 126: 1-48. gs Bown, P. R., Rutledge, D. C., Crux, J. A. & Gallagher, L. T. (1998). Lower Cretaceous. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series . 86-131. gs OReferences:
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Octocyclus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 19-6-2025
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=10808 Go to Archive.is to create a permanent copy of this page - citation notes |
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