Tribrachiatus orthostylus


Classification: Coccolithophores -> Nannolith families inc sed -> Rhomboasteraceae -> Tribrachiatus -> Tribrachiatus orthostylus
Sister taxa: T. contortus, T. digitalis, T. orthostylus, T. sp.,

Taxonomy:

Citation: Tribrachiatus orthostylus Shamrai, 1963
Rank: Species
Variants:
Synonyms:
Notes & discussion: The name T. orthostylus is "nom. subst. pro Discoaster tribrachiatus Bramlette & Riedel ; see ICBN Art. 55" according to Loeblich & Tappan 1966). This is probably because the combination Tribrachiatus tribrachiatus would have been a tautonym (both parts the same) which is not permitted under the ICBN. The type specimen and description of T. orthostylus is thus that of D. tribrachiatus

Distinguishing features: Large, single-cycle tri-radiate nannoliths with little or no ray end bifurcation (<25% of the total arm length).

Farinacci & Howe catalog pages: Tribrachiatus orthostylus [no catalog entry yet], Discoaster tribrachiatus * , Discoaster rotans * , Rhomboaster weii * ,

Search data:
TagsLITHS: nannolith-radiate, star-shaped,
CSPH: not known, V-UNITS: all, R-UNITS: none, DETAILS: 1ou,
MetricsLith size: 8->13µm; Segments: 3->3;
Sources: lith size from OD & illustrated specimens
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): within NP12 zone (50.50-53.70Ma, top in Ypresian stage). Data source: Perch-Nielsen 1985b
First occurrence (base): near top of NP10 zone (90% up, 54.3Ma, in Ypresian stage). Data source: Agnini et al. 2007 fig 8, 9

Plot of occurrence data:

  • Histogram - Neptune occurrence data from DSDP and ODP proceedings. Pale shading <50 samples in time bin. Interpret with caution & read these notes
  • Note to users in China - the diagram may not plot unless you use a VPN since I use google services on the website. If this is a problem please contact me 谢谢.
  • Taxon plotted: Tribrachiatus orthostylus, synonyms included - Discoaster tribachiatus; Marthasterites tribrachiatus; Rhomboaster orthostylus; Tribrachiatus orthostylus; space-time plot :: Samples map :: Parent: Tribrachiatus

    References:

    Agnini, C., Fornaciari, E., Raffi, I., Rio, D., Rohl, U. & Westerhold, T. (2007). High-resolution nannofossil biochronology of middle Paleocene to early Eocene at ODP Site 1262: Implications for calcareous nannoplankton evolution. Marine Micropaleontology. 64: 215-248. gs

    Bramlette, M. N. & Riedel, W. R. (1954). Stratigraphic value of discoasters and some other microfossils related to Recent coccolithophores. Journal of Paleontology. 28: 385-403. 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. US Geological Survey professional paper. 1554: 1-36. gs

    Bybell, L. & Self-Trail, J. (1997). Late Paleocene and Early Eocene calcareous nannofossils from three boreholes in an onshore-offshore transect from New Jersey to the Atlantic continental rise. Proceedings of the Ocean Drilling Program. Scientific Results. 150: 91-110. gs

    Loeblich, A. R. & Tappan, H. (1966). Annotated index and bibliography of the calcareous nannoplankton. Phycologia. 5: 81-216. gs

    Perch-Nielsen, K. (1985a). Cenozoic calcareous nannofossils. In, Bolli, H. M. , Saunders, J. B. & Perch-Nielsen, K. (eds) Plankton Stratigraphy. Cambridge University Press, Cambridge 427-555. gs

    Shamrai, I. A. (1963). Nekotorye formy verkhnemelovykh i paleogenovykh kokkolitov i disko_asterov na yuge russkol platformy [Certain forms of Upper Cretaceous and Paleogene coccoliths and discoasters from the southern Russian Platform]. Izv. Vyssh. Ucheb. Zaved. Geol. i Razv. 6(4): 27-40. gs


    nannotaxlogo400px

    Tribrachiatus orthostylus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 20-7-2019

    Taxon Search:
    Advanced Search

    Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=1431 Go to Archive.is to create a permanent copy of this page - citation notes



    Comments (0)

    No comments yet. Be the first!

    Add Comment

    * Required information
    1000
    Captcha Image
    Powered by Commentics