pforams@mikrotax - Braunella brauni

nmn

Braunella brauni

Classification: pf_mesozoic -> Heterohelicidae -> Braunella -> Braunella brauni
Sister taxa: B. brauni, B. punctulata, B. sp.

Taxonomy

Citation: Braunella brauni Georgescu 2007

Rank: Species

Basionym: Braunella brauni

Type images:

holotype: B. brauni
holotype: B. brauni
holotype: B. brauni
holotype & paratypes: B. brauni
paratype: B. brauni
paratype: B. brauni
paratype: B. brauni
paratype: B. brauni
topotype: B. brauni
topotype: B. brauni
x: B. brauni
x: B. brauni

Original description: Test biserial throughout, chamber proliferation not observed in any of the studied specimens. Chambers are subspherical throughout, those of the earlier part of the test increase rapidly in size. Kummerform lastformed chambers are common. The rate of chamber growth is lower in the adult stage. The two rows of biserially arranged chambers are slightly divergent in some specimens. Sutures are distinct, depressed, and perpendicular to slightly oblique to the growth axis of the test. Periphery is broadly rounded, without any peripheral structures. Main aperture is in the shape of a low to, more rarely, a medium high arch at the base of the last-formed chambers. It is bordered in the central part by an imperforate band and two detached rod-like rims symmetrically arranged on the two sides of the test. The detached rims define additional apertures along the zigzag suture in the portion of the last-formed one to four chambers. Test ornamentation is irregularly reticulate, costate ornamentation being present on the last-formed one to two chambers of some specimens. Test wall is calcareous, hyaline, and finely perforate, pore diameter being in the range of 1.9-2.5 microns.

Entries in the Catalog of original descriptions: Braunella brauni

Geological Range:
Last occurrence (top): within P. hariaensis zone (66.39-67.30Ma, top in Maastrichtian stage). Data source: [copied from Chronos database]
First occurrence (base): within G. havanensis zone (74.00-75.71Ma, base in Campanian stage). Data source: [copied from Chronos database]

Plot of range and 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
(NB There is no histogram as there are no occurrence records for the taxon in the Neptune database) Parent: Braunella

Character matrix

test outline:	Subtriangular	chamber arrangement:	Biserial	edge view:	Equally biconvex	aperture:	Interiomarginal
sp chamber shape:	Globular	coiling axis:	N/A	periphery:	N/A	aperture border:	Thin porticus
umb chbr shape:	Globular	umbilicus:	N/A	periph margin shape:	Broadly rounded	accessory apertures:	N/A
spiral sutures:	Moderately depressed	umb depth:	N/A	wall texture:	Coarsely costate	shell porosity:	Finely Perforate: 1-2.5µm
umbilical or test sutures:	Moderately depressed	final-whorl chambers:	2.0-2.0	N.B. These characters are used for advanced search. N/A - not applicable

References:

Georgescu, M. D. (2007b). Taxonomic re-evaluation of the Late Cretaceous serial planktonic foraminifer Gümbelina punctulata Cushman, 1938 and related species. Revista Española de Micropaleontología. 39: 1-14. gs V O

Braunella brauni compiled by the pforams@mikrotax project team viewed: 28-2-2021

Taxon Search:

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Short stable page link: https://mikrotax.org/pforams/index.php?id=110033 Go to Archive.is to create a permanent copy of this page - citation notes

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