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Hedbergella roblesae


Classification: pf_mesozoic -> Hedbergellidae -> Hedbergella -> Hedbergella roblesae
Sister taxa: << < 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, 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 roblesae (Obregon, 1959)
Rank: Species
Basionym: Globigerina roblesae
Taxonomic discussion: This species displays a rather wide morphological variability mainly regarding the number of chambers (4.5 to 6) 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 the height of the spire which can range from low to moderately high. [copied from Chronos database]

Type images:

Original description: Translation from Spanish: Detached test, slightly club-shaped and trochospiral, the peripheral margin is lobate; five chambers are visible on the dorsal side, the first chambers are globular, the last ones are elongated, sutures are curved; the wall texture is calcareous, slightly perforated and pustulose, the aperture is extraumblical umbilical equatorial and arch-shaped.

Entries in the Catalog of original descriptions: Globigerina roblesae


Emended description: Test medium sized, trochospirally coiled; 5, rarely 4.5 to 6 chambers in the outer whorl, increasing rapidly but gradually in size as added; chambers initially globular to subglobular, the last two or three moderately to strongly elongate; chambers round at their end; spiral side low to medium-high; peripheral outline ovoid and strongly lobate; sutures straight to slightly curved on both spiral and umbilical sides; umbilicus rather wide 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:Wideperiph margin shape:Narrowly roundedaccessory apertures:N/A
    spiral sutures:Strongly depressedumb depth:Shallowwall texture:Smoothshell porosity:Finely Perforate: 1-2.5┬Ám
    umbilical or test sutures:Strongly depressedfinal-whorl chambers:5.0-6.0 N.B. These characters are used for advanced search. N/A - not applicable

    References:

    Obregon, J. d. l. P. (1959). Consideraciones sobre el daniano en la Cuenca sedimentaria de Tampico-Misantla. Mexicana de Geologos Petroleros. 11(01-Feb): 13-20. gs


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    Hedbergella roblesae compiled by the pforams@mikrotax project team viewed: 8-12-2019

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    Short stable page link: http://mikrotax.org/pforams/index.php?id=110260 Go to Archive.is to create a permanent copy of this page - citation notes



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