pforams@mikrotax - Planohedbergella messinae

Planohedbergella messinae


Classification: pf_mesozoic -> Globigerinelloididae -> Planohedbergella -> Planohedbergella messinae
Sister taxa: P. aspera, P. circularis, P. escheri, P. impensa, P. messinae, P. multispina, P. prairiehillensis, P. subcarinata, P. ultramicra, P. yaucoensis

Taxonomy

Citation: Planohedbergella messinae (Brönnimann, 1952)
Rank: species
Basionym: Globigerinella messinae messinae Bronnimann, 1952
Synonyms:
Taxonomic discussion: junior synonym of Globigerinelloides asper (EHRENBERG)
Bronnimann stated that it is distinguished from G. voluta by its much smaller size and distinctly laterally compressed, finely ornamented chambers and by the large arcuate aperture with lip-like projection, which in G. voluta is a "thin lunate opening in the suture on the margin of the last chamber". Because there is considerable size and shape variability in this taxon, the two species are considered synonymous with G. volutus as the senior synonym because of priority.

Type images:

Original description: "The small and compressed test with its more or less lobate outline is semi-involute and planispiral in the adult, though occasionally developing a tendency toward a weak trochoidal spiral. The test throughout is closely coiled. The adult volution comprises five, rarely six, chambers. They are peripherally rounded and laterally somewhat compressed, and increase in size rapidly. The outline of the chambers is elongate-ellipsoid in apertural view and subcircular in umbilical view. The shallow umbilici are partly covered with the prolongations of the delicate lip-like projections of the apertural border. In the well-preserved individuals they exhibit portions of the early ontogenetic volutions. No details of shape and arrangement of the innermost chambers are recognizable. The straight sutures are deep and well marked. The large arcuate aperture issituated equatorially at the base of the end chamber. The aperture is surrounded with delicate lip-like projections extending into the umbilici. The walls appear to be thin and finely perforate. Minute papillae are evenly distributed over the surface. Early chambers are more strongly ornamented."

Entries in the Catalog of original descriptions: Globigerinella messinae messinae


Emended description:


Morphology:

Wall type:

Size:

Character matrix
test outline:Lobatechamber arrangement:Planispiraledge view:Hourglassaperture:Equatorial
sp chamber shape:Globularcoiling axis:Very lowperiphery:N/Aaperture border:Thin lip
umb chbr shape:Globularumbilicus:Narrowperiph margin shape:Broadly roundedaccessory apertures:Relict
spiral sutures:Strongly depressedumb depth:Shallowwall texture:Finely muricateshell porosity:-
umbilical or test sutures:Strongly depressedfinal-whorl chambers:4.5-5.5 N.B. These characters are used for advanced search. N/A - not applicable

Most likely ancestor: Planohedbergella escheri - at confidence level 3 (out of 5). Data source: Huber et al. 2022 fig. 2.
Likely descendants: Planohedbergella subcarinata; plot with descendants

Geological Range:
Last occurrence (top): within Maastrichtian Stage (66.04-72.05Ma, top in Maastrichtian stage). Data source: [copied from Chronos database]
First occurrence (base): within D. asymetrica zone (84.19-86.71Ma, base in Coniacian stage). Data source: Huber et al. 2022

Plot of range and occurrence data:

References:

Huber, B. T., Petrizzo, M. M. & Falzoni, F. (2022). Taxonomy and phylogeny of Albian–Maastrichtian planispiral planktonic foraminifera traditionally assigned to Globigerinelloides. Micropaleontology. 68(2): 117-183. gs


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Planohedbergella messinae compiled by the pforams@mikrotax project team viewed: 5-12-2022

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Short stable page link: https://mikrotax.org/pforams/index.php?id=110139 Go to Archive.is to create a permanent copy of this page - citation notes



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