ODP Site 1050-154~b.JPG
TDP-154.JPG
Robaszynski et al 1979_7f1-154.JPG
TDP-153~a.JPG
Robaszynski et al 1979_7f2-154.JPG
Eicher Worstell 1970_12f1-269.JPG
Falzoni et al 2016 f05-11.JPG
ODP Site 1050-154~a.JPG
ODP Site 1050-154~b.JPG
TDP-154.JPG
Robaszynski et al 1979_7f1-154.JPG
TDP-153~a.JPG
Robaszynski et al 1979_7f2-154.JPG
Eicher Worstell 1970_12f1-269.JPG
Falzoni et al 2016 f05-11.JPG
ODP Site 1050-154~a.JPGTaxonomy
holotype: R. praehelvetica
holotype: R. praehelvetica
paratype: R. praehelvetica
paratype: R. praehelvetica
paratype: R. praehelvetica
paratype: R. praehelveticaOriginal description: The shape of the test of R. praehelvetica is rotaloid, spiral side flattened, about 2.5 whorls constituting the spire, in transverse section the individual whorls are rounded on the spiral side and in some specimens the latter part of the ultimate whorl becomes somewhat angular, with the inner whorls occasionally raised to a common level above the outer whorls. The periphery is lobulate, and the edge is very broadly rounded. There are usually 5-6 chambers in the ultimate whorl that are quite inflated and increase rather rapidly in size as added. Sutures are calcareous, perforate, and with varying degrees of rugosity, but usually only faintly so. The umbilicus is deep and rather wide. Aperture is interiomarginal, opening into the umbilicus and often covered by a platelike extension of the final chamber. About 95% of the studied specimens coil dextrally.
Entries in the Catalog of original descriptions: Rugoglobigerina praehelvetica
Geological Range:
Last occurrence (top): within H. helvetica zone (92.56-93.52Ma, 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 range and occurrence data:
Character matrix
| test outline: | Circular | chamber arrangement: | Trochospiral | edge view: | Spiroconvex | aperture: | Interiomarginal |
| sp chamber shape: | Inflated | coiling axis: | Low-moderate | periphery: | N/A | aperture border: | Thick lip |
| umb chbr shape: | Inflated | umbilicus: | Wide | periph margin shape: | Broadly rounded | accessory apertures: | None |
| spiral sutures: | Moderately depressed | umb depth: | Deep | wall texture: | shell porosity: | Finely Perforate: 1-2.5µm | |
| umbilical or test sutures: | Moderately depressed | final-whorl chambers: | 5.0-6.0 | N.B. These characters are used for advanced search. N/A - not applicable | |||
Eicher, D. L. & Worstell, P. (1970). Lunatriella, a Cretaceous heterohelicid foraminifer from the western interior of the United States. Micropaleontology. 16(1): 117-121. 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 Trujillo, E. F. (1960). Upper Cretaceous foraminifera from near Redding, Shasta County, California. Journal of Paleontology. 34: 290-346. gsReferences:
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Helvetoglobotruncana praehelvetica compiled by the pforams@mikrotax project team viewed: 23-1-2021
Short stable page link: http://mikrotax.org/pforams/index.php?id=110277 Go to Archive.is to create a permanent copy of this page - citation notes |