Taxonomy
Original description: Test broad and rounded, about 1½ times as broad, initial portion rapidly tapering, later portion of nearly uniform width, periphery of early portion keeled, later indented; chambers of the early portion somewhat compressed, keeled, much broader than high, rapidly inflated in the adult where they are globular; sutures in the early portion slightly costate or with the fine perforations in vertical lines, in the adult thicker-walled with the surface rather coarsely punctate; aperture, a low, broad arch with a slight lip, the sides continuing in flange onto the preceding chamber.
Entries in the Catalog of original descriptions: Guembelina punctulata, Pseudotextularia echevarriai, Heterohelix (Heterohelix) planeobtusa, Heterohelix robusta
Emended description:
Character matrix
test outline: | Subtriangular | chamber arrangement: | Biserial | edge view: | Compressed | aperture: | Interiomarginal |
sp chamber shape: | Inflated | coiling axis: | N/A | periphery: | N/A | aperture border: | Thin flange |
umb chbr shape: | Inflated | umbilicus: | N/A | periph margin shape: | Broadly rounded | accessory apertures: | None |
spiral sutures: | Moderately depressed | umb depth: | N/A | wall texture: | Finely costate | shell porosity: | Finely Perforate: 1-2.5µm |
umbilical or test sutures: | Moderately depressed | final-whorl chambers: | 2-2 | N.B. These characters are used for advanced search. N/A - not applicable |
Geological Range:
Last occurrence (top): within P. hariaensis zone (66.39-67.64Ma, top in Maastrichtian stage). Data source: [copied from Chronos database]
First occurrence (base): within R. calcarata zone (75.06-75.91Ma, base in Campanian stage). Data source: [copied from Chronos database]
Plot of range and occurrence data:
Cushman, J. A. (1938). Cretaceous species of Guembelina and related genera. Contributions from the Cushman Laboratory for Foraminiferal Research. 14: 2-28. gs Georgescu, M. D. (2007b). Taxonomic re-evaluation of the Late Cretaceous serial planktonic foraminifer Gümbelina punctulata Cushman, 1938 and related species. Revista Española de Micropaleontología. 39: 1-14. gs Nederbragt, A. J. (1991). Late Cretaceous biostratigraphy and development of Heterohelicidae (planktic foraminifera). Micropaleontology. 37: 329-372. gs Pessagno, E. A. (1967). Upper Cretaceous planktonic foraminifera from the western Gulf Coastal Plain. Palaeontographica Americana. 5: 245-445. gs O Missing or ambiguous references: Georgescu 2007; References:
Braunella punctulata compiled by the pforams@mikrotax project team viewed: 14-12-2024
Short stable page link: https://mikrotax.org/pforams/index.php?id=110034 Go to Archive.is to create a permanent copy of this page - citation notes |
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