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Guembelitria turrica from: Kroon, D.Nederbragt, A.J. (1990): Ecology and Paleoecology of Triserial Planktic Foraminifera . Marine Micropaleontology Vol. 16 p. 25-38
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Anonymous: Unedited TaxonConcept data
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Species Guembelitria turrica


Diagnosis / Definition:
Kroon & Nederbragt (1990):
Test small, triserial, or with 2.5 to 3 chambers per whorl; hyaline, finely perforate. Chambers globulose to slightly compressed; sutures depressed. Wall covered with small, triangular pustules concentrated on the chambers of the first few whorls; pores scattered all over the test, in between the pustules. Aperture a medium sized arc at the base of the last formed chamber, bordered by a distinct lip and slightly asymmetric. A small toothplate is present. Size of holotype: 155 Bm high, 95 ]xm wide; paratypes between 150 and 175 ttm high, 95 to 110 Bm wide.
Discussion / Comments:
Kroon & Nederbragt (1990):
The shape of the ultimate chamber may vary, from globular, having a symmetric aperture, to elongate (buliminid-shaped) with a distinctly asymmetric aperture. Such chambers are interpreted to represent a terminal stage, comparable to the "gerontic" multiserial growth ofG. vivans. Some specimens resemble the prebuliminids in general shape (Plate III, 7), but differ from this group of smoothwalled benthics in having its wall covered with pustules. Furthermore, such forms are endmembers of a range of variation that includes types with a typical Guembelitria morphology, i.e. with globular chambers and a slightly asymmetric aperture. Guembelitria turrita differs from G. cretacea and G. cenomana in ornamentation, while the dimensions of its aperture are intermediate between those of G. cenomana and G. cretacea. Guembelitria turrita differs from G. columbiana in having the pustules concentrated on the chambers of the first whorls. The name G. turrita derives from the latin "turritus", which means "shaped as a tower". Type locality and type level: Grand Banks Imperial Oil drill hole 23, at 45°28'N, 53°33'W, at a depth of 283-286 m (samples 75-15, 75-16 and 75-17 from a 3 m cored interval). The presence of the benthic species Bolivinoides draco miliaris Hiltermann and Koch and Neoflabelline praereticulata Hiltermann gives a Late Campanian or Early Maastrichtian age. Planktic foraminiferal markers are absent.
Systematics:

29
 Genus Guembelitria
  Species Guembelitria turrica
Synonym list:
Kroon & Nederbragt (1990):
1990 Guembelitria turrica . - Kroon & Nederbragt : p.36 pl. 3, figs. 3, 8 (holotype); pl. 3, figs. 1, 2, 4-7, 9, 10 (paratypes)
References:

Kroon,D. and Nederbragt,A.J. (1990):
Ecology and Paleoecology of Triserial Planktic Foraminifera . Marine Micropaleontology Vol. 16 p. 25-38
Anonymous: Unedited TaxonConcept data
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This work is licensed under a Creative Commons Attribution 2.5 License.