pforams@mikrotax - Praeorbulina

pforams@mikrotax - Praeorbulina pforams@mikrotax - Praeorbulina

Praeorbulina

Classification: pf_cenozoic -> Globigerinidae -> Praeorbulina
Sister taxa: Beella, Globigerina, Globigerinella, Protentella, Quiltyella ⟩⟨ Ciperoella, Globigerinoides, Globigerinoidesella, Globoturborotalita, Orbulina, Praeorbulina, Sphaeroidinella, Sphaeroidinellopsis, Trilobatus, Turborotalita ⟩⟨ Dentoglobigerina, Globoquadrina ⟩⟨ Catapsydrax, Clavatorella, Paragloborotalia, Protentelloides ⟩⟨ Eoglobigerina, Globigerinatheka, Globorotaloides, Guembelitrioides, Orbulinoides, Parasubbotina, Pseudoglobigerinella, Subbotina

Daughter taxa (time control age-window is: 0-800Ma)
			Praeorbulina circularis Test nearly spherical; last chamber enveloping >75% of the earlier test; sutural apertures circular to subcircular.
			Praeorbulina glomerosa Test ovoid to nearly spherical; last chamber enveloping >40% of the earlier test; sutural apertures small crescentic and slitlike
			Praeorbulina curva Test, subspherical to spherical, last chamber enveloping 40 to 70% of the earlier test; sutural apertures, small, few (4 to 8).
			Praeorbulina sp. Specimens which cannot be assigned to established species

Taxonomy

Citation: Praeorbulina Olsson 1964

taxonomic rank: genus

Type species: Globigerinoides glomerosa glomerosa Blow 1956

Taxonomic discussion: Olsson (1964) proposed the genus Praeorbulina to include intermediate morphological stages connecting Globigerinoides sicanus with Orbulina universa. The species and subspecies now referred to as Praeorbulina were originally included in the genus Globigerinoides (Blow, 1956) and later placed in Porticulasphaera (Bolli, 1957b; Blow, 1959). Praeorbulina differs from Orbulina by the lack of areal apertures and from Globigerinoides in lacking a distinct umbilicus and an umbilical aperture in the adult stage. Lipps (1964) considered Praeorbulina Olsson as a junior synonym of Candorbulina. [Kennett & Srinivasan 1983]

Catalog entries: Praeorbulina

Distinguishing features:
Parent taxon (Globigerinidae): Wall spinose, usually with 3½-6 globular chambers in final whorl, trochospiral or planispiral
This taxon: Terminal chamber partially enveloping previous chambers

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.
They are being edited as the site is developed and comments on them are especially welcome.

Description

Biogeography and Palaeobiology

Geographic distribution

Phylogenetic relations

The genus Praeorbulina is geographically widespread from tropical to temperate areas and is a short-ranging index form diagnostic of levels close to the Early Miocene-Middle Miocene boundary. A bioseries within Praeorbulina extends from Praeorbulina glomerosa curva -> glomerosa glomerosa -> glomerosa circularis and in turn into Orbulina suturalis and O. universa. Since the evolution is continuous, the distinction between the phylogenetic species is gradational. [Kennett & Srinivasan 1983]

Most likely ancestor: Trilobatus - at confidence level 4 (out of 5). Data source: Kennett & Srinivasan 1983.
Likely descendants: Orbulina; plot with descendants

Biostratigraphic distribution

Geological Range:
Last occurrence (top): at top of N9 zone (100% up, 14.2Ma, in Langhian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within M5a subzone (16.27-16.38Ma, base in Burdigalian stage). Data source: Total of ranges of species in this database

Plot of occurrence data:

Range-bar - range as quoted above, pink interval top occurs in, green interval base occurs in.
Triangles indicate an event for which a precise placement has been suggested
Neptune data: This is a higher taxon page so Neptune data is not plotted. See also: customisable plot Parent: Globigerinidae

Primary source for this page: Kennett & Srinivasan 1983, p.81

References:

Blow, W. H. (1956). Origin and evolution of the foraminiferal genus Orbulina d'Orbigny. Micropaleontology. 2(1): 57-70. gs

Blow, W. H. (1959). Age, correlation, and biostratigraphy of the upper Tocuyo (San Lorenzo) and Pozon Formations, eastern Falcon, Venezuela. Bulletins of American Paleontology. 39(178): 67-251. gs

Bolli, H. M. (1957a). Planktonic foraminifera from the Eocene Navet and San Fernando formations of Trinidad. In, Loeblich, A. R. , Jr., Tappan, H., Beckmann, J. P., Bolli, H. M., Montanaro Gallitelli, E. & Troelsen, J. C. (eds) Studies in Foraminifera. U.S. National Museum Bulletin . 215: 155-172. gs

Kennett, J. P. & Srinivasan, M. S. (1983). Neogene Planktonic Foraminifera. Hutchinson Ross Publishing Co., Stroudsburg, Pennsylvania. 1-265. gs

Lipps, J. H. (1964). Miocene planktonic foraminifera from Newport Bay, California. Tulane Studies in Geology and Paleontology. 2: 109-133. gs O

Olsson, R. K. (1964a). Praeorbulina Olsson, a new foraminiferal genus. Journal of Paleontology. 4: 770-771. gs

Praeorbulina compiled by the pforams@mikrotax project team viewed: 7-10-2024

Taxon Search:

Advanced Search

Short stable page link: https://mikrotax.org/pforams/index.php?id=104196 Go to Archive.is to create a permanent copy of this page - citation notes

Add Comment

Comments (2)

Bridget Wade

Olsson reference should be:

OLSSON, R. K., 1964. Praeorbulina Olsson, a new foraminiferal genus.

Journal of Paleontology, 4: 770–771.

6 January 2019 16:41

Jeremy Young(UK)

thanks - i'll correct that - jeremy

6 January 2019 22:42