nmn

Marginotruncana angusticarenata


Classification: pf_mesozoic -> Globotruncanidae -> Marginotruncana -> Marginotruncana angusticarenata
Sister taxa: M. angusticarenata, M. caronae, M. coronata, M. desioi, M. manaurensis, M. marginata, M. paraconcavata, M. pileoliformis, M. pseudolinneiana, M. renzi, M. schneegansi, M. sigali, M. sigmoconcavata, M. sinuosa, M. tarfayaensis, M. undulata, M. sp.,

Taxonomy

Citation: Marginotruncana angusticarenata (Gandolfi, 1942)
Rank: Species
Basionym: Globotruncana linnei var. angusticarenata

Type images:

Original description: Non si osserva nei nostri sedimenti una così grande variazione come descrive DE LAPPARENT. Peraltro una ciscreta varìabilità è anche qui osservabile soprattutto per quanto riguarda la convessità della cohchiglia: Anche la cavità ombelicale è più o meno larga, talvolta notevolmente minore che in certe figure di DE LAPPARENT. Pertanto gli individui qui presenti si lasciano separare in .due gruppi, naturalmente uniti da tutti i passaggi possibili
1. conchiglia piatta, camere pure piane, faccia settale alta, listelli lontani l'uno dall'altro. Tale forma può essere più o meno larga, i rapporti tra diametro e altezza possono variare, ma tutte si. accostano bene alla G. linnei tipica (forma tipica di DE LAPPARENT);
2. conchiglia più o meno biconvessa, avvolgimento trocoide, faccia settale generalmente molto stretta, listelli molto riavvicinati, talvolta anche difficilmente distinguibili -l'uno dall'altro: angusticarinata.

Entries in the Catalog of original descriptions: Globotruncana linnei angusticarenata


Emended description: Pessagno, 1967, p. 300: "Test trochospiral, spiroconvex with narrow double keel following peripheral margin. Primary aperture extraumbilical-umbilical to nearly umbilical in position with well developed portici when well preserved. Five to eight chambers in last whorl, petaloid to elongate spirally. Sutures separating chambers both spirally and umbilicall curved, slightly raised. Ourter wall radial hyaline perforate except for double keel, which is radial hyaline imperforate. Septal walls microgranular hyaline, perforate. Portici microgranular hyaline, perforate (?). [copied from Chronos database]

Geological Range:
Last occurrence (top): within D. concavata zone (86.71-89.91Ma, top in Coniacian stage). Data source: [copied from Chronos database]
First occurrence (base): within M. schneegansi zone (89.91-92.56Ma, base in Turonian 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

  • (NB There is no histogram as there are no occurrence records for the taxon in the Neptune database) Parent: Marginotruncana

    Character matrix

    test outline:Circularchamber arrangement:Trochospiraledge view:Inequally biconvexaperture:
    sp chamber shape:Crescenticcoiling axis:Low-moderateperiphery:Double keelaperture border:Coalescing portici
    umb chbr shape:Crescenticumbilicus:Narrowperiph margin shape:Narrowly roundedaccessory apertures:None
    spiral sutures:Raisedumb depth:Shallowwall texture:Smoothshell porosity:Finely Perforate: 1-2.5┬Ám
    umbilical or test sutures:final-whorl chambers:5.0-8.0 N.B. These characters are used for advanced search. N/A - not applicable

    References:

    Gandolfi, R. (1942). Ricerche micropaleontologiche e stratigraphfiche sulla Scaglia e sul flysch Cretacici dei Dintorni di Balerna (Canton Ticino). Rivista Italiana di Paleontologia. 48: 1-160. gs

    Postuma, J. A. (1971). Manual of planktonic foraminifera. Elsevier for Shell Group, The Hague. 1-406. gs


    logo

    Marginotruncana angusticarenata compiled by the pforams@mikrotax project team viewed: 24-10-2019

    Taxon Search:
    Advanced Search

    Short stable page link: http://mikrotax.org/pforams/index.php?id=110329 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