Beella praedigitata


Classification: pf_cenozoic -> Globigerinidae -> Beella -> Beella praedigitata
Sister taxa: B. digitata, B. megastoma, B. praedigitata, B. sp.,

Taxonomy

Citation: Beella praedigitata (Parker, 1967)
Rank: species
Basionym: Globigerina praedigitata Parker, 1967
Taxonomic discussion: B. praedigitata and B. megastoma seem to be  poorly differentiated and so possibly are synonyms

Catalog entries: Globigerina praedigitata

Type images:

Distinguishing features: Low to medium trochospiral, lobulate periphery; wall smooth

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: Low to medium trochospiral, lobulate periphery

Aperture: Interiomarginal umbilical semicircular arch bordered by a pronounced lip [Aze 2011, based on Kennett & Srinivasan 1983]


Wall type: Spinose; Smooth [Aze 2011]

Test morphology: Test low to medium trochospiral, equatorial periphery strongly lobulate; cham- bers inflated, initially spherical , later becoming ovate, 4 to 5, rapidly increasing chambers in the final whorl; sutures distinct, depressed; surface smooth with circular to subcircular pores and discrete tubercles representing spine bases (PI. 58; Fig. 2). Aperture interiomarginal, umbilical , a semicircular arch bordered by a pronounced lip. [Kennett & Srinivasan 1983]

Character matrix

test outline:Lobatechamber arrangement:Trochospiraledge view:Spiroconvexaperture:Umbilical
sp chamber shape:Elongatecoiling axis:Low-moderateperiphery:N/Aaperture border:Thick lip
umb chbr shape:Globularumbilicus:Wideperiph margin shape:Broadly roundedaccessory apertures:None
spiral sutures:Moderately depressedumb depth:Deepwall texture:Cancellateshell porosity:Macroperforate: >2.5µm
umbilical or test sutures:Strongly depressedfinal-whorl chambers:4.0-5.0 N.B. These characters are used for advanced search. N/A - not applicable

Biogeography and Palaeobiology


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

[SCOR WG138]


Isotope paleobiology: Aze et al. 2011 ecogroup 4 - Open ocean sub-thermocline. Based on comparison with other species of the genus

Phylogenetic relations: B. praedigitata evolved from Globigerina (Gg.) bulloides in the Late Miocene. [Kennett & Srinivasan 1983]

Similar species: B. praedigitata differs from its descendant B. digitata by lacking fully developed radially elongate chambers. [Kennett & Srinivasan 1983]

Most likely ancestor: Globigerinella siphonifera - at confidence level 4 (out of 5). Data source: Molecular genetic data (Andre et al. 2014, Weiner et al. 2015) indicates that modern B. digitata is the sister group of G. sacculifer, and so B. praedigitata is likely to have evolved from G. siphonifera/praesiphonifera. This was also indicated by Aze et al. (2011), although without documentation. Previously it was thought to have evolved from G. bulloides - Kennett & Srinivasan 1983, fig.26; Chaisson & Pearson 1997 p.29..
Likely descendants: Beella digitata;

Biostratigraphic distribution

Geological Range:
Last occurrence (top): within PT1b subzone (0.00-0.61Ma, top in "Holocene" stage). Data source: Chaisson & Pearson (1997)
First occurrence (base): within N17a zone (6.60-8.58Ma, base in Tortonian stage). Data source: Kennett & Srinivasan 1983

Plot of occurrence data:

Primary source for this page: Kennett & Srinivasan 1983, p.232

References:

André, A. et al. (2014). SSU rDNA Divergence in Planktonic Foraminifera: Molecular Taxonomy and Biogeographic Implications. PLoS One. 9: e104641-. gs

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

Chaisson, W. P. & Pearson, P. N. P. (1997). Planktonic foraminifer biostratigraphy at Site 925: Middle Miocene–Pleistocene. Proceedings of the Ocean Drilling Program, Scientific Results,. 154: 3-31. gs

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

Parker, F. L. (1967). Late Tertiary biostratigraphy (planktonic foraminifera) of tropical Indo-Pacific deep-sea cores. Bulletins of American Paleontology. 52(235): 115203-. gs

Weiner, A. K. M., Weinkauf, M. F. G., Kurasawa, A., Darling, K. F. & Kucera, M. (2015). Genetic and morphometric evidence for parallel evolution of the Globigerinella calida morphotype. Marine Micropaleontology. 114: 19-35. gs


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Beella praedigitata compiled by the pforams@mikrotax project team viewed: 22-10-2019

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Short stable page link: http://mikrotax.org/pforams/index.php?id=104004 Go to Archive.is to create a permanent copy of this page - citation notes



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