Fohsella praefohsi


Classification: pf_cenozoic -> Globorotaliidae -> Fohsella -> Fohsella praefohsi
Sister taxa: F. paralenguaensis, F. lenguaensis, F. robusta, F. lobata, F. fohsi, F. praefohsi, F. peripheroacuta, F. peripheroronda,

Taxonomy

Citation: Fohsella praefohsi (Blow & Banner, 1966)
Rank: species
Basionym: Globorotalia (Globorotalia) praefohsi Blow & Banner, 1966
Synonyms:

Catalog entries: Globorotalia (Globorotalia) praefohsi,

Type images:

Distinguishing features: Like G. peripheroacuta but with a keel (imperforate carina) on the final 1 or 2 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


Diagnostic characters: Biconvex, low trochospiral, equatorial periphery lobulate with partly developed keel

Aperture: : Umbilical-extraumbilical low arch with prominent lip [Aze 2011, based on Kennett & Srinivasan 1983]


Wall type: Non-spinose; Smooth [Aze 2011]

Test morphology: Test low trochospiral, equatorial periphery slightly lobulate, axial periphery acute with a partly developed keel on last two chambers; chambers compressed, six to seven in the final whorl, increasing slowly in size; sutures on spiral side curved, gently raised, onumbilicalsidecurved toradial,depressed; surface distinctly and uniformly perforate; umbilicus narrow, aperture umbilical-extraumbilical with a low arch bordered by a prominent lip. [Kennett & Srinivasan 1983]

Character matrix

test outline:Ovatechamber arrangement:Trochospiraledge view:Inequally biconvexaperture:Umbilical-extraumbilical
sp chamber shape:Crescenticcoiling axis:Lowperiphery:Single keelaperture border:Thick lip
umb chbr shape:Subtriangularumbilicus:Narrowperiph margin shape:Subangularaccessory apertures:None
spiral sutures:Weakly depressedumb depth:Shallowwall texture:Smoothshell porosity:Macroperforate: >2.5µm
umbilical or test sutures:Weakly depressedfinal-whorl chambers:6.0-8.0 N.B. These characters are used for advanced search. N/A - not applicable

Biogeography and Palaeobiology


Geographic distribution: Tropical to warm subtropical. [Kennett & Srinivasan 1983] Low latitudes [Aze et al. 2011, based on Kennett & Srinivasan (1983)]

[SCOR WG138]


Isotope paleobiology: Aze et al. 2011 ecogroup 3 - Open ocean thermocline. Based on light ∂13C and relatively heavy ∂18O. Sources cited by Aze et al. 2011 (appendix S3): Keller (1985); Hodell & Vayavananda (1993); Pearson & Shackleton (1995)

Phylogenetic relations: Gr. (F.) praefohsi differs from Gr. (F.) peripheroacuta in possessing a keel (imperforate carina) in the last one or two chambers of the final whorl. It differs from Gr. (F.) fohsi fohsi in exhibiting a keel only on the last few chambers. The early chambers of the final whorl are noncarinate. Thus Gr. (F.) praefohsi is a partly keeled form between nonkeeled intermediate Gr. (F.) peripheroacuta and the fully keeled Gr. (F.) fohsi fohsi.
Stainforth et al. (1975) considered Gr. (F.) peripheroacuta and Gr. (F.) praefohsi as intraspecific variants of Gr. (F.) fohsi fohsi, but all of these forms are useful phylogenetic species. [Kennett & Srinivasan 1983]

Most likely ancestor: Fohsella peripheroacuta - at confidence level 4 (out of 5). Data source: Kennett & Srinivasan 1983, fig. 12.
Likely descendants: Fohsella fohsi;

Biostratigraphic distribution

Geological Range:
Notes: The evolutionary appearance of this taxon marks the base of Zone N11 (Blow, 1969) or of zone M8 of Wade et al. (2011)
Last occurrence (top): within N12 zone (11.79-13.41Ma, top in Serravallian stage). Data source: Kennett & Srinivasan 1983
First occurrence (base): at base of M8 zone (0% up, 13.8Ma, in Serravallian stage). Data source: Wade et al. (2011), zonal marker

Plot of occurrence data:

Primary source for this page: Kennett & Srinivasan 1983, p.98

References:

Aze, T. et al. (2011). A phylogeny of Cenozoic macroperforate planktonic foraminifera from fossil data. Biological Reviews. 86: 900-927. gs

Blow, W. H. & Banner, F. T. (1966). The morphology, taxonomy and biostratigraphy of Globorotalia barisanensis LeRoy, Globorotalia fohsi Cushman and Ellisor, and related taxa. Micropaleontology. 12(3): 286-302. gs

Hodell, D. A. & Vayavananda, A. (1993). Middle Miocene paleoceanography of the western equatorial Pacific (DSDP Site 289) and the evolution of Globorotalia (Fohsella). Marine Micropaleontology. 22: 279-310. gs

Keller, G. (1985). Depth stratification of planktonic foraminifers in the Miocene Ocean. In, Kennett, J. P. (ed.) The Miocene Ocean: Paleoceanography and Biogeography. GSA Memoir. 163: 1-337. gs

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

Pearson, P. N. & Shackleton, N. J. (1995). Neogene multispecies planktonic foraminifer stable isotope record, Site 871, Limalok Guyot. Proceedings of the Ocean Drilling Program, Scientific Results. 401-410. gs

Wade, B. S., Pearson, P. N., Berggren, W. A. & Pälike, H. (2011). Review and revision of Cenozoic tropical planktonic foraminiferal biostratigraphy and calibration to the geomagnetic polarity and astronomical time scale. Earth-Science Reviews. 104: 111-142. gs


logo

Fohsella praefohsi compiled by the pforams@mikrotax project team viewed: 20-7-2019

Taxon Search:
Advanced Search

Short stable page link: http://mikrotax.org/pforams/index.php?id=104123 Go to Archive.is to create a permanent copy of this page - citation notes



Comments (0)

No comments yet. Be the first!

Add Comment

* Required information
1000
Captcha Image
Powered by Commentics