Sphaeroidinella dehiscens


Classification: pf_cenozoic -> Globigerinidae -> Sphaeroidinella -> Sphaeroidinella dehiscens
Sister taxa: S. dehiscens, S. sp.,

Taxonomy

Citation: Sphaeroidinella dehiscens (Parker & Jones, 1865)
Rank: species
Basionym: Sphaeroidina bulloides var. dehiscens Parker & Jones, 1865
Variants:

Catalog entries: Sphaeroidina bulloides dehiscens, Sphaeroidina dehiscens immatura, Sphaeroidinella ionica ionica, Sphaeroidinella dehiscens excavata

Type images:

Distinguishing features: monospecific

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: Large, trochospiral, equatorial periphery ovoid or spherical with smooth secondary cortex

Aperture: Primary aperture interiomarginal umbilical two sutural supplementary apertures bordered by crenulated lip [Aze 2011, based on Kennett & Srinivasan 1983]

Coiling direction (in extant population): mixed


Wall type: Non-spinose; Cancellate with smooth cortex [Aze 2011]

Test morphology: Test large, trochospiral compact, equatorial periphery broadly ovoid or spherical; chambers 3 in the final whorl , strongly inflated, subglobular, becoming increasingly embracing in the adult; sutures flush, covered by secondary thickening; primary surface coarsely perforate similar to Globigerinoides sacculifer (PI. 51, Fig. 2), which is covered by secondary thickening. The secondary covering reduced the external openings of the pores, thus rendering the surface a smooth and glossy appearance; umbilicus deep, irregular; primary aperture interiomarginal, umbilical, one or two sutural supplementary apertures present; apertures bordered by crenulated lip, which are extensions of the cortex. [Kennett & Srinivasan 1983]

Size: >250µm

Character matrix

test outline:Ovatechamber arrangement:Trochospiraledge view:Equally biconvexaperture:Umbilical
sp chamber shape:Petaloidcoiling axis:Low-moderateperiphery:N/Aaperture border:Thin flange
umb chbr shape:Petaloidumbilicus:Wideperiph margin shape:Broadly roundedaccessory apertures:Sutural
spiral sutures:Flushumb depth:Deepwall texture:Smoothshell porosity:Macroperforate: >2.5µm
umbilical or test sutures:Weakly depressedfinal-whorl chambers:3.0-3.0 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)]

In modern oceans a common, warm water, species [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): Shackleton & Vincent (1978)

Phylogenetic relations: Sa. dehiscens evolved directly from Sphaeroidinellopsis paenedehiscens by developing a small, supplementary aperture at the chamber suture contact on the spiral side. By definition, this marks the change from Sphaeroidinellopsis to Sphaeroidinella and defines the base of Zone N19. [Kennett & Srinivasan 1983]

Molecular Genotypes recognised (data from PFR2 database, June 2017), one genotype only from 6 sequences. Reference: André et al. 2014.

Most likely ancestor: Sphaeroidinellopsis paenedehiscens - at confidence level 4 (out of 5). Data source: Kennett & Srinivasan 1983, fig 23..

Biostratigraphic distribution

Geological Range:
Last occurrence (top): Extant Data source: present in the plankton (SCOR WG138)
First occurrence (base): near base of PL1 [Atl.] zone (12% up, 5.6Ma, in Messinian stage). Data source: Wade et al. (2011), additional event; position within zone determined by linear interpolation from data in table 1 of Wade et al. (2011).

Plot of occurrence data:

Primary source for this page: Kennett & Srinivasan 1983, p.212

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

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

Loeblich, A. & Tappan, H. (1994). Foraminifera of the Sahul shelf and Timor Sea. Cushman Foundation for Foraminiferal Research, Special Publication. 31: 1-661. gs

Norris, R. D. (1998). Planktonic foraminifer biostratigraphy: Eastern Equatorial Atlantic. Proceedings of the Ocean Drilling Program, Scientific Results. 159: 445-479. gs

Parker, W. K. & Jones, T. R. (1865). On some foraminifera from the North Atlantic and Arctic Oceans, including Davis Straits and Baffin's Bay. Philos. Trans. R. Soc. London.. 155: 325-441. gs

Pearson, P. N. (1995). Planktonic foraminifer biostratigraphy and the development of pelagic caps on guyots in the Marshall Islands group. Proceedings of the Ocean Drilling Program, Scientific Results. 144: 21-59. gs

Postuma, J. A. (1971). Manual of planktonic foraminifera. Elsevier for Shell Group, The Hague. 1-406. gs

Shackleton, N. J. & Vincent, E. (1978). Oxygen and carbon isotope studies in Recent Foraminifera from the southeast Indian Ocean. Marine Micropaleontology. 3: 1-13. gs


logo

Sphaeroidinella dehiscens compiled by the pforams@mikrotax project team viewed: 22-10-2019

Taxon Search:
Advanced Search

Short stable page link: http://mikrotax.org/pforams/index.php?id=104213 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