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Praeglobotruncana algeriana


Classification: pf_mesozoic -> Hedbergellidae -> Praeglobotruncana -> Praeglobotruncana algeriana
Sister taxa: P. algeriana, P. clotensis, P. compressa, P. delrioensis, P. gibba, P. hilalensis, P. inermis, P. kalaati, P. oraviensis, P. pseudoalgeriana, P. shirakinensis, P. stephani, P. sp.,

Taxonomy

Citation: Praeglobotruncana algeriana (Caron, 1966) Falzoni et al., 2016
Rank: Species
Basionym: Praeglobotruncana algeriana
Synonyms:
Dicarinella algeriana (Caron, 1966)

Type images:

Original description: Translated from French: Diagnosis: We quote here the very thorough diagnosis given by M. Reichel (1949) for the original description of Globotruncana aff. renzi (renamed P. algeriana by Caron, ) "The spire comprises a total number of 16 chambers occupying a little more than two and a half whorls, 6 of them occupying the last whorl. Keels or pustulose ridges border the septa of the spiral side, from the first chambers to the 11th or 12th chamber, the peripheral keel is double. The first of the 6 chambers of the last whorl is still bordered by two keels consisting of small pustules. In the two specimens studied the second chamber of the last whorl is undeveloped (too small for the rank it occupies) and has only one thick keel reminiscent of that of G. stephani Gandolfi; the following four chambers are single keeled, but in the vicinity of the septal suture the carinal ridge splits into two diverging branches, the upper branch forming the septal ridge of the spiral side, the lower branch blurs within the sutural groove of the umbilical side. The last chamber has only a blunt keel, barely noticeable. One sees that in a similar form the axial sections will generally show the typical profile of G. renzi (with a last single-keeled chamber) However, if by chance, the section crosses the point where the keel splits in one of the last chambers, the section will lead us to believe that we are dealing with a fully bicarinate form. The main aperture is not quite visible, however it does not extend much beyond the umbilicus. Fairly developed peristomal tongue-like flaps converge in the umbilical depression, leaving between them small, deep indentations. No accessory apertures."

Entries in the Catalog of original descriptions: Praeglobotruncana algeriana

Geological Range:
Last occurrence (top): within M. schneegansi zone (89.91-92.56Ma, top in Turonian stage). Data source: [copied from Chronos database]
First occurrence (base): within R. cushmani zone (94.03-95.94Ma, base in Cenomanian 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

Character matrix

test outline:Subcircularchamber arrangement:Trochospiraledge view:Spiroconvexaperture:Umbilical-extraumbilical
sp chamber shape:Crescenticcoiling axis:Moderateperiphery:Double keelaperture border:Thin porticus
umb chbr shape:Trapezoidalumbilicus:Wideperiph margin shape:Subangularaccessory apertures:Intralaminal
spiral sutures:Raised beadedumb depth:Shallowwall texture:Finely pustuloseshell 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:

Caron, M. (1966). Globotruncanidae du Cretace superieur du synclinal de la Gruyere (Prealpes medianes, Suisse). Revue de Micropaléontologie. 9(2): 68-93. gs

Falzoni, F., Petrizzo, M. R., Jenkyns, H. C., Gale, A. S. & Tsikos, H. (2016). Planktonic foraminiferal biostratigraphy and assemblage composition across the Cenomanian–Turonian boundary interval at Clot Chevalier (Vocontian Basin, SE France). Cretaceous Research. 59: 69-97. gs

Robaszynski, F., Caron, M. & le Groupe de Travail Européen des Foraminifères Planctoniques (1979). Atlas des Foraminiféres Planctoniques du Crétace Moyen (Mer Boréale et Téthys). Cahiers de Micropaléontologie. 1 & 2: 1-185. gs


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Praeglobotruncana algeriana compiled by the pforams@mikrotax project team viewed: 30-9-2020

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Short stable page link: http://mikrotax.org/pforams/index.php?id=110426 Go to Archive.is to create a permanent copy of this page - citation notes



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