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Hedbergella semielongata


Classification: pf_mesozoic -> Hedbergellidae -> Hedbergella -> Hedbergella semielongata
Sister taxa: << < H. infracretacea, H. kuhryi, H. kuznetsovae, H. labocaensis, H. luterbacheri, H. maslakovae, H. mitra, H. modesta, H. occulta, H. praelippa, H. praetrocoidea, H. primare, H. quadricamerata, H. roblesae, H. ruka, H. semielongata, H. sigali, H. similis, H. speetonensis, H. tardita, H. tatianae, H. trocoidea, H. tunisiensis, H. tuschepsensis, H. sp.,

Taxonomy

Citation: Hedbergella semielongata Longoria 1974
Rank: Species
Basionym: Hedbergella semielongata
Taxonomic discussion: This species displays a rather wide morphological variability mainly regarding the number of chambers (4 to 4.5) in the outer whorl, the number of elongate chambers and their elongation degree, the peripheral outline which can be more or less strongly lobate and especially the height of the spire which can range from low to moderately high. [copied from Chronos database]

Type images:

Original description: Test small, formed by 3 whorls; peripheral margin substellate; 5-6 chambers in the last whorl increasing gradually in size as added; chambers inflated, early chambers ovate, final chambers subelongate on both spiral and umbilical sides, ovoid in peripheral view; sutures radial, slightly curved on both spiral and umbilical sides; primary aperture extraumbilical to spiroumbilical in position; umbilicus narrow.

Entries in the Catalog of original descriptions: Hedbergella semielongata


Emended description: Test medium sized, trochospirally coiled; 4 to 4.5 chambers in the outer whorl, increasing rather randomly in size as added; chambers initially globular to subglobular, usually the last two radially elongate; in some specimens elongation may even interest all the chambers of the last whorl; chambers round at their end; spiral side low to moderately high; peripheral outline cross-shaped and strongly lobate; sutures straight to slightly curved on both spiral and umbilical sides; umbilicus rather small and shallow; aperture as a low extraumbilical arch reaching the periphery. Wall smooth and finely perforate. [copied from Chronos database]

Geological Range:
Last occurrence (top): within G. algerianus zone (118.93-122.17Ma, top in Aptian stage). Data source: [copied from Chronos database]
First occurrence (base): within H. similis zone (128.73-130.37Ma, base in Barremian 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: Hedbergella

    Character matrix

    test outline:Stellatechamber arrangement:Trochospiraledge view:Equally biconvexaperture:
    sp chamber shape:Elongatecoiling axis:Very lowperiphery:N/Aaperture border:Thin lip
    umb chbr shape:Elongateumbilicus:Narrowperiph margin shape:Moderately roundedaccessory apertures:N/A
    spiral sutures:Strongly depressedumb depth:Shallowwall texture:Smoothshell porosity:Finely Perforate: 1-2.5µm
    umbilical or test sutures:Strongly depressedfinal-whorl chambers:4.0-4.5 N.B. These characters are used for advanced search. N/A - not applicable

    References:

    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 semielongata compiled by the pforams@mikrotax project team viewed: 28-1-2020

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    Short stable page link: http://mikrotax.org/pforams/index.php?id=110262 Go to Archive.is to create a permanent copy of this page - citation notes



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