Specimens which cannot be assigned to established species
| Daughter taxa (time control age-window is: 0-800Ma) | ||||
| | | Laeviheterohelix dentata | |
| Laeviheterohelix flabelliformis | |||
| | | Laeviheterohelix glabrans | |
| | | Laeviheterohelix pulchra | |
| | Laeviheterohelix reniformis | ||
| | | Laeviheterohelix turgida | |
| Laeviheterohelix sp. Specimens which cannot be assigned to established species | ||||
Taxonomy
Original description: Diagnosis: Test calcareous, biserial throughout or with an initial planispiral coil; wall microperforate and smooth with scattered pustules, or with pores situated in the center of a pore mound. Aperture a simple arc, bordered by distinct flanges.
Entries in the Catalog of original descriptions: Laeviheterohelix
Distinguishing features:
Parent taxon (Heterohelicidae): Aperture symmetrical, ranging from a low slit to a high arch at the base of the final chamber, becoming terminal in uniserial taxa.
This taxon: Biserial throughout, aperture symmetrically positioned, wall smooth, microperforate with irregularly scattered pustule or pore mounds
Geological Range:
Last occurrence (top): in upper part of Maastrichtian Stage (79% up, 67.3Ma, in Maastrichtian stage). Data source: Total of range of species in this database
First occurrence (base): near base of Turonian Stage (9% up, 93.5Ma, in Turonian stage). Data source: Total of range of species in this database
Plot of range and occurrence data:
Nederbragt, A. J. (1991). Late Cretaceous biostratigraphy and development of Heterohelicidae (planktic foraminifera). Micropaleontology. 37: 329-372. gsReferences:
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Laeviheterohelix compiled by the pforams@mikrotax project team viewed: 4-6-2023
Short stables page link: https://mikrotax.org/pforams/index.php?id=110300 Go to Archive.is to create a permanent copy of this page - citation notes |
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