| Daughter taxa: (blue => in age window 0-300Ma) | ||||
| | | Test compact, nearly involute, globular; aperture asymmetrical equatorial; Clavigerinella-type reticulate wall texture and thickened crust. | |
| Specimens which cannot be assigned to established species | ||||
Hillebrandt (1976) first proposed that “Subbotina inaequispira” (= Parasubbotina inaequispira) was the ancestral species to Pseudohastigerina globulosa Hillebrandt ( =Pseudoglobigerinella bolivariana). Blow (1979) also regarded inaequispira as the ancestral species of the lineage, leading to bolivariana through Globorotalia (Turborotalia) griffinae Blow ( =Parasubbotina griffinae). Both Blow (1979) and Toumarkine and Luterbacher (1985) made the interesting observation that inaequispira also gave rise to the Clavigerinella lineage at about the same time (i.e., Biochron E7). The high porosity, reticulate, Clavigerinella-type wall texture of both Clavigerinella and Pseudoglobigerinella n. gen. is shared with P. inaequispira, in which it apparently first developed. [Olsson et al. 2006]
Catalog entries: Pseudoglobigerinella;
Type images:Distinguishing features: Inflated, nearly involute, globular test, asymmetrical equatorial aperture; wall reticulate, Clavigerinella-type wall texture. May show uncoiling.
NB These concise distinguishing features statements are used in the tables of daughter-taxa to act as quick summaries of the differences between e.g. species of one genus.
Diagnostic characters: Pseudoglobigerinella n. gen. is identified by its inflated, nearly involute, globular test, asymmetrical equatorial aperture, and the reticulate, Clavigerinella-type wall texture and thickened crust. A tendency towards uncoiling occurs in some morphotypes of the genus.
[Olsson et al. 2006]
Wall type: Normal perforate, spinose, high porosity, reticulate, Clavigerinella-type wall structure, covered by a thick crust in adult stage. [Olsson et al. 2006]
Test morphology: Globular, nearly involute, asymmetrically planispiral in adult stage (juvenile stage
very low trochospiral), slightly lobulate in outline, chambers globular; 4-5 globular, embracing chambers in final whorl, increasing rapidly in size, ultimate chamber much inflated, sutures moderately depressed, straight, umbilicus small and often covered by ultimate chamber; in edge view chambers globular in shape, slightly embracing, aperture asymmetrically equatorial, varying from a low arch to a high distinctive arch, bordered by an imperforate rim and sometimes by a narrow lip that broadens on both sides towards the center of the coil.
Size: Maximum diameter of type species 0.52 mm, thickness 0.40 mm.
ETYMOLOGY.— Named for its resemblance to modern Globigerinella.
[Olsson et al. 2006]
Most likely ancestor: Parasubbotina - at confidence level 0 (out of 5). Data source: .
Geological Range:
Last occurrence (top): near top of Lutetian Stage (89% up, 41.9Ma, in Lutetian stage). Data source: Total of range of species in this database
First occurrence (base): in upper part of Ypresian Stage (71% up, 50.2Ma, in Ypresian stage). Data source: Total of range of species in this database
Plot of occurrence data:
Primary source for this page: Olsson et al. 2006 - Eocene Atlas, chap. 5, p. 105
Blow, W.H., (1979). The Cainozoic Globigerinida: A study of the morphology, taxonomy, evolutionary relationships and stratigraphical distribution of some Globigerinida (mainly Globigerinacea), 2. E. J. Brill, Leiden, 1413 pp. Hillebrandt, A., (1976). Los foraminiferos planctonicos, nummulitidos y coccolitoforidos de la zona de Globorotalia palmerae del Cuisiense (Eoceno inferior) en el SE de Espana, (Provincias de Murcia y Alicante. Revista Española de Micropaleontología, 8(3): 323-394. Olsson, R.K.; Pearson, P.N. & Huber, B.T., (2006). Taxonomy, biostratigraphy, and phylogeny of Eocene Catapsydrax, Globorotaloides, Guembelitrioides, Paragloborotalia, Parasubbotina, and Pseudoglobigerinella n. gen. In: Pearson, P.N. et al. (Editors), Atlas of Eocene Planktonic Foraminifera, Cushman Foundation Special Publication 41. Cushman Foundation Special Publication. 41 Allen Press, Lawrence, Kansas, pp. 67-110. Petters, V., (1954). Tertiary and Upper Cretaceous foraminifera from Colombia, S. A. Contributions from the Cushman Foundation for Foraminiferal Research, 5(1): 37-41.References:
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Pseudoglobigerinella compiled by the pforams@mikrotax project team viewed: 22-9-2018
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