Distinguishing features:
Parent taxon (Tegulalithus): Cylindrical nannoliths, typically with flanges at both ends and so cotton-reel-shaped in side view.
This taxon: Cylindrical nannoliths with wall formed from a single cycle of ~16 elements and a lid (or flange) at each end formed from overlapping, concentric cycles of diamond-shaped elements. In side view the overall shape is cotton-reel-like.
Bown_etal_1998 EK 5-06-15.jpg
Bown_etal_1998 EK 5-06-16.jpg
Crux86 INANewsl fig1.JPG
Crux86 INANewsl fig2.JPG
KPC Tegulalithus septentrionalis.JPG
Stradner et al 2010_Fig-92b.jpg
Varol1992pl2-16.JPG
Varol1992pl2-17.JPG
Varol1992pl2-18.JPG
Varol1992pl2-19.JPG
Varol1992pl2-20.JPG
Bown_etal_1998 EK 5-15-10.jpg
Crux86 INANewsl fig3.JPG
Crux86 INANewsl fig4.JPG
Varol1992pl5-19.JPG
Varol1992pl5-20.JPG
Bown_etal_1998 EK 5-15-11.jpg
Crux86 INANewsl fig5.JPG
TypeFig Tegulalithus septentrionalis.jpgTaxonomy:
Eprolithus septentrionalis (Stradner 1963) Perch-Nielsen 1984
Farinacci & Howe catalog pages: L. septentrionalis *
Distinguishing features:
Parent taxon (Tegulalithus): Cylindrical nannoliths, typically with flanges at both ends and so cotton-reel-shaped in side view.
This taxon: Cylindrical nannoliths with wall formed from a single cycle of ~16 elements and a lid (or flange) at each end formed from overlapping, concentric cycles of diamond-shaped elements. In side view the overall shape is cotton-reel-like.
Resembles a nannoconid in XPL, but is easily differentiated in PC, and in side view. There is variation in the size and development of the flanges (formed by the proximal and distal plates overhanging the wall), however, the proximal and distal flanges are always equally developed.
Morphology:
Size:
Ecology & Biogeography
Biology & life-cycles
Phylogenetic relations
| LITHS: nannolith-radiate, cylindrical, CA: closed, CROSS-POLARS: T-prominent, |
| Lith size: 4->8µm; Segments: 15->20; Data source notes: illustrated specimens |
See also: Nannoconus pseudoseptentrionalis - rather similar Nannoconid;
Geological Range:
Last occurrence (top): at top of BC10 zone (100% up, 132.7Ma, in Hauterivian stage). Data source: Bown et al. 1998 - zonal marker
First occurrence (base): at base of BC9 zone (0% up, 133Ma, in Hauterivian stage). Data source: Bown et al. 1998 - zonal marker
Plot of occurrence data:
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 O Crux, J. A. (1986). Tegulalithus, a new genus of Early Cretaceous calcareous nannofossils. INA Newsletter. 8(2): 88-90. gs V O Perch-Nielsen, K. (1984b). Validation of new combinations. INA Newsletter. 6(1): 42-46. gs V O Rutledge, D. & Bown, P. R. (1996). New names for old: taxonomic clarification of some Early Cretaceous nannofossil marker-species. Journal of Nannoplankton Research. 18(2): 53-59. gs V O Stradner, H. (1963). New contributions to Mesozoic stratigraphy by means of nannofossils. In, Proceedings of the Sixth World Petroleum Congress. Section 1 Paper 4: 167-183. gs Stradner, H., Aubry, M. -P. & Bonnemaison, M. (2010). Calcareous nannofossil type specimens in the collection of the Geological Survey of Austria: A taxonomic and stratigraphic update. Jahrbuch der Geologischen Bundesanstalt. 150(1-2): 9-84. gs V O Varol, O. (1992b). Taxonomic revision of the Polycyclolithaceae and its contribution to Cretaceous biostratigraphy. Newsletters on Stratigraphy. 27(93-127): -. gsReferences:
 |
Tegulalithus septentrionalis compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 5-2-2023
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=11195 Go to Archive.is to create a permanent copy of this page - citation notes |
Comments
(0)