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Spiroplecta americana


Classification: pf_mesozoic -> Heterohelicidae -> Spiroplecta -> Spiroplecta americana
Sister taxa: S. americana, S. sp.,

Taxonomy

Citation: Spiroplecta americana Ehrenberg 1844
Rank: Species
Basionym: Spiroplecta americana
Synonyms:

Type images:

Original description: "Test minute and subtriangular in side view, the biserial portion flaring widely from the tiny planispiral coil, periphery broadly rounded; the 5-6 chambers of the coil are low and not much inflated, the later 6-11 biserially arranged chambers increasing rapidly in height so that later ones are inflated and subglobular; sutures distinct, straight, somewhat oblique, depressed; wall calcareous, hyaline, surface faintly striate, finely perforate; aperture a low arch at the inner margin of the final chamber, sometimes with a slight lip."

Entries in the Catalog of original descriptions: Spiroplecta americana, Heterohelix navarroensis

Geological Range:
Last occurrence (top): within P. hariaensis zone (66.39-67.30Ma, top in Maastrichtian stage). Data source: [copied from Chronos database]
First occurrence (base): within R. calcarata zone (75.71-76.18Ma, base in Campanian stage). Data source: [copied from Chronos database]

Plot of occurrence data:

Dec 2017 - Plotting of Neptune data has been re-enabled on the Mesozoic pages following revision of the age-models in Neptune. The data is, however, still very sparse for the Early Cretaceous

  • 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: Spiroplecta americana, synonyms included - Guembelina navarroensis; Heterohelix navarroensis;
  • space-time plot :: Samples map :: Parent: Spiroplecta

    Character matrix

    test outline:Subtriangularchamber arrangement:Biserialedge view:Compressedaperture:Interiomarginal
    sp chamber shape:Inflatedcoiling axis:N/Aperiphery:N/Aaperture border:Thin flange
    umb chbr shape:Inflatedumbilicus:N/Aperiph margin shape:Broadly roundedaccessory apertures:None
    spiral sutures:Moderately depressedumb depth:N/Awall texture:Finely costateshell porosity:-
    umbilical or test sutures:Moderately depressedfinal-whorl chambers:2.0-2.0 N.B. These characters are used for advanced search. N/A - not applicable

    References:

    Ehrenberg, C. G. (1844). Über 2 neue Lager von Gebirgsmassen aus Infusorien als Meers-Absatz in Nord-Amerika und eine Vergleichung derselben mit den organischen Kreidegebilden in Europa und Afrika. Bericht k. preuss. Akad. Wiss. Berlin. 57-97. gs

    Nederbragt, A. J. (1991). Late Cretaceous biostratigraphy and development of Heterohelicidae (planktic foraminifera). Micropaleontology. 37: 329-372. gs

    Smith, C. C. & Pessagno, E. A. (1973). Planktonic foraminifera and stratigraphy of the Corsicana formation (Maestrichtian) North-central Texas. Cushman Foundation for Foraminiferal Research, Special Publication. 12: 1-67. gs


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    Spiroplecta americana compiled by the pforams@mikrotax project team viewed: 18-10-2019

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    Short stable page link: http://mikrotax.org/pforams/index.php?id=110536 Go to Archive.is to create a permanent copy of this page - citation notes



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