Taxonomy
Original description: Translated from French: The test is slightly trochospiral, biconvex and with a weakly lobate periphery. About 20 chambers forming 3 whorls. Rapid increase in size for the 6 chambers of the last whorl. On the spiral side, the semicircular or angular sutures of the chambers meet the internal whorl obliquely; they are curved backwards. The last sutures have a tendency to become radial. Six to 7 reniform chambers visible on the umbilical side. The size of the wide umbilicus, is about a 1/3 of the diameter. The aperture is interiomarginal-umbilical in position. The double keel splits into two only toward the septal side.
Entries in the Catalog of original descriptions: Globotruncana tarfayaensis
Character matrix
| test outline: | Subcircular | chamber arrangement: | Trochospiral | edge view: | Inequally biconvex | aperture: | Umbilical-extraumbilical |
| sp chamber shape: | Petaloid | coiling axis: | Low-moderate | periphery: | Double keel | aperture border: | Coalescing portici |
| umb chbr shape: | Crescentic | umbilicus: | Wide | periph margin shape: | Subangular | accessory apertures: | |
| spiral sutures: | Raised beaded | umb depth: | Shallow | wall texture: | Smooth | shell porosity: | Microperforate: <1µm |
| umbilical or test sutures: | Raised beaded | final-whorl chambers: | 6-7 | N.B. These characters are used for advanced search. N/A - not applicable | |||
Geological Range:
Last occurrence (top): within D. asymetrica zone (83.65-85.60Ma, top in Santonian stage). Data source: [copied from Chronos database]
First occurrence (base): within M. schneegansi zone (89.75-92.51Ma, base in Turonian stage). Data source: [copied from Chronos database]
Plot of range and occurrence data:
Lehmann, R. (1963). Étude des Globotruncanidés du Crétacé supérieur de la province de Tarfaya (Maroc occidental). Notes du Service Geologique du Maroc. 21(156): 133-179. gsReferences:

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Marginotruncana tarfayaensis compiled by the pforams@mikrotax project team viewed: 18-5-2026
Short stable page link: https://mikrotax.org/pforams/index.php?id=110344 Go to Archive.is to create a permanent copy of this page - citation notes |
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