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Hedbergella excelsa


Classification: pf_mesozoic -> Hedbergellidae -> Hedbergella -> Hedbergella excelsa
Sister taxa: H. aptiana, H. bizonae, H. bollii, H. compacta, H. excelsa, H. gorbachikae, H. handousi, H. hexacamerata, H. hispaniae, H. infracretacea, H. kuhryi, H. kuznetsovae, H. labocaensis, H. luterbacheri, H. maslakovae, H. mitra, H. modesta, H. occulta, H. praelippa, H. praetrocoidea, > >>

Taxonomy

Citation: Hedbergella excelsa Longoria 1974
Rank: Species
Basionym: Hedbergella excelsa

Type images:

Original description: Test small to medium size, formed by about 3 whorls; earlier whorls coiled in higher plane than final whorl; peripheral margin circular; generally with 6 chambers in the last whorl, increasng gradually in size as added; chambers spherical to ovoid on both spiral and umbilical sides; spherical in peripheral view; ultimate chamber protruding towards the umbilicus; sutures radial, straight, depressed on both spiral and umbilical sides; umbilicus narrow and circular.

Entries in the Catalog of original descriptions: Hedbergella excelsa


Emended description: Test small to medium, coiled in a high to very high trochospire; 2 to 2.5 whorls; 5 to 6 chambers (exceptionally 4.5) in the outer whorl increasing gradually and slowly in size as added; chambers globular to subglobular, the last two or three possibly becoming slightly reniform in lateral view; equatorial periphery circular to subcircular, slightly to moderately lobate; sutures depressed, radial to slightly curved; umbilical area small and rather deep; aperture as a low to medium arch bordered by a lip. Wall smooth, finely perforate, that may be covered by perforation cones in the early chambers of the last whorl. [Huber & Leckie,2011, p. 66]: Emended description. Test wall finely perforate, covered by weakly developed perforation cones. Test small to medium in size, coiled in a moderate to high trochospire with 2 to 2.5 whorls; 4.5 to 6 chambers in the final whorl, increasing gradually in size, chambers globular to subglobular; equatorial periphery circular to subcircular, moderately lobate; sutures depressed, radial to slightly curved; umbilical area narrow and moderately deep; aperture an umbilical-extraumbilical low to medium arch with an imperforate rim but without a bordering lip or other periapertural structures. [copied from Chronos database]

Geological Range:
Last occurrence (top): at top of P. rohri zone (95% up, 113.5Ma, in Aptian stage). Data source: Huber and Leckie, 2011
First occurrence (base): within G. blowi zone (125.71-128.73Ma, base in Barremian stage). Data source: Coccioni and Premoli Silva, 1994

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: Hedbergella

    Character matrix

    test outline:Lobatechamber arrangement:Trochospiraledge view:Spiroconvexaperture:-
    sp chamber shape:Inflatedcoiling axis:Moderate-highperiphery:N/Aaperture border:Thin lip
    umb chbr shape:Inflatedumbilicus:Narrowperiph margin shape:Broadly roundedaccessory apertures:N/A
    spiral sutures:Moderately depressedumb depth:Deepwall texture:Smoothshell porosity:Finely Perforate: 1-2.5µm
    umbilical or test sutures:Moderately depressedfinal-whorl chambers:6.0-6.5 N.B. These characters are used for advanced search. N/A - not applicable

    References:

    Huber, B. T. & Leckie, R. M. (2011). Planktic foraminiferal species turnover across deep-sea Aptian/Albian boundary sections. Journal of Foraminiferal Research. 41: 53-95. gs

    Longoria, J. F. (1974). Stratigraphic, morphologic and taxonomic studies of Aptian planktonic foraminifera. Revista Española de Micropaleontología. Numero Extraordinario: 5-107. gs


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    Hedbergella excelsa compiled by the pforams@mikrotax project team viewed: 3-4-2020

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    Short stable page link: http://mikrotax.org/pforams/index.php?id=110241 Go to Archive.is to create a permanent copy of this page - citation notes



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