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Hedbergella tunisiensis


Classification: pf_mesozoic -> Hedbergellidae -> Hedbergella -> Hedbergella tunisiensis
Sister taxa: << < 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 tunisiensis (Boudagher-Fadel, 1995)
Rank: Species
Basionym: Blefusciana speetonensis tunisiensis

Type images:

Original description: Diagnosis: This subspecies differs from B. speetonensis speetonensis in having a more involute spiral side with more curved intercameral sutures on the spiral side and an apertural porticus extending right over the periphery and reaching the last three chambers of the last whorl on the spiral side.

Description: Test about 0.28mm in diameter, a low trochospire with five to six chambers in the last whorl. The spiral side is almost completely involute and concave. Last three chambers show a beginning of asymmetry, highest in their posterior part. The sutures are depressed, curved on the spiral side and virtually radial on the umbilical side. The aperture is a low arch, has a porticus throughout its length, broadest posteriorly. The surface of the test is smooth, microperforate except for the umbilical shoulders, which may be imperforate.

Entries in the Catalog of original descriptions: Blefuscuiana speetonensis tunisiensis

Geological Range:
Last occurrence (top): within H. planispira zone (111.84-113.26Ma, top in Albian stage). Data source: [copied from Chronos database]
First occurrence (base): within H. planispira zone (111.84-113.26Ma, base in Aptian 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:Circularchamber arrangement:Trochospiraledge view:Concavo-convexaperture:Equatorial
    sp chamber shape:Globularcoiling axis:Lowperiphery:N/Aaperture border:Thin lip
    umb chbr shape:Globularumbilicus:Wideperiph margin shape:Broadly roundedaccessory apertures:None
    spiral sutures:Strongly depressedumb depth:Shallowwall texture:Smoothshell porosity:Macroperforate: >2.5┬Ám
    umbilical or test sutures:Strongly depressedfinal-whorl chambers:4.0-6.0 N.B. These characters are used for advanced search. N/A - not applicable

    References:

    BouDagher-Fadel, M. K. (1995). The planktonic Foraminifera of the Early Cretaceous of Tunisia compared to those of western and central Tethys. Paleopelagos. 5: 137-159. gs


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    Hedbergella tunisiensis compiled by the pforams@mikrotax project team viewed: 12-12-2019

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    Short stable page link: http://mikrotax.org/pforams/index.php?id=110270 Go to Archive.is to create a permanent copy of this page - citation notes



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