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Asterohedbergella


Classification: pf_mesozoic -> Hedbergellidae -> Asterohedbergella
Sister taxa: Asterohedbergella, Clavihedbergella, Costellagerina, Falsotruncana, Hedbergella, Helvetoglobotruncana, Liuenella, Microhedbergella, Muricohedbergella, Paracostellagerina, Paraticinella, Praeglobotruncana, Pseudoguembelitria, Whiteinella,
Daughter taxa: (blue => in age window 0-800Ma)

Specimens which cannot be assigned to established species

Taxonomy

Citation: Asterohedbergella Hamaoui 1964
Rank: Genus
Basionym: Hedbergella (Asterohedbergella)
Type species: Hedbergella (Asterohedbergella) asterospinosa Hamaoui, 1964

Original description: Test free, concavo-convex to unequally biconvex, trochospirally coiled throughout, spiral side evolute, umbilical side involute, with true umbilicus, with or without pseudoumbilicus, peripheral margin rounded to acute, without carina! band. At least each adult chamber drawn out at the periphery into a conical or flask-shaped, tapering extension which may produce a variably oriented true tubulospine, never inflated terminally. The earliest chambers may be subglobular. The surface of the test may be finely hispid. but without rugosities or costellae. Wall structure calcitic, radiate, finely perforate, lamellar. Aperture a low arch, interiomarginal, extraumbilical-umbilical, bordered by a narrow lip, but lacking tegilla.

Family Globotruncanidae; subfamily Rotaliporinae. Cenomanian. Monotypic.

Entries in the Catalog of original descriptions: Hedbergella (Asterohedbergella)

Distinguishing features: Test in a low trochospiral coil, early chambers globular, increasing rapidly in size, those of the final whorl pyriform to subconical and may terminate in a tubulospine, resulting in a stellate peripheral outline, umbilical side deeply excavated centrally, sutures radial, depressed, periphery angular but lacking an imperforate carinal band; wall calcareous, radiate, finely perforate, surface smooth to finely hispid but without costellae; aperture a low interiomarginal arch, extraumbilical-umbilical, bordered by a narrow lip.

Geological Range:
Last occurrence (top): within Cenomanian Stage (93.90-100.50Ma, top in Cenomanian stage). Data source: Total of range of species in this database
First occurrence (base): within Cenomanian Stage (93.90-100.50Ma, base in Cenomanian stage). Data source: Total of range of species in this 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

References:

Loeblich, A. R. & Tappan, H. (1988). Foraminiferal Genera and Their Classification (Volume I-II). Van Nostrand Reinhold Co., New York. 1-1059. gs


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Asterohedbergella compiled by the pforams@mikrotax project team viewed: 18-1-2020

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Short stable page link: http://mikrotax.org/pforams/index.php?id=110017 Go to Archive.is to create a permanent copy of this page - citation notes



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