pforams@mikrotax - Planoheterohelix moremani

pforams@mikrotax - Planoheterohelix moremani pforams@mikrotax - Planoheterohelix moremani

Planoheterohelix moremani

Classification: pf_mesozoic -> Heterohelicidae -> Planoheterohelix -> Planoheterohelix moremani
Sister taxa: P. globulosa, P. moremani, P. olssoni, P. papula, P. paraglobulosa, P. planata, P. postmoremani, P. praenuttallii, P. reussi, P. rumseyensis ⟩⟨ P. labellosa, P. sphenoides, P. stenopos, P. vistulaensis, P. sp.

ODP Site 1050-158~c.JPG
ODP Site 1050-158~a.JPG
ODP Site 1050-158~b.JPG
ODP Site 1050-158~d.JPG
ODP Site 1050-158~e.JPG
DSDP Site 511-158.JPG
Falzoni et al 2016 f05-08.JPG
Nederbragt 1991_2f6-7-158.JPG
Nederbragt 1991_3f1-2-158.JPG
Pessagno 1967 pl48 10-11.JPG
TDP-158.JPG

Taxonomy

Citation: Planoheterohelix moremani (Cushman, 1938)

Rank: Species

Basionym: Guembelina moremani

Synonyms: Guembelina boliviniformis

Taxonomic discussion: Multiserial growth may be present as a terminal stage. Georgescu & Huber. 2009, p.81: "The holotype (USNM 307959), which is deposited in the Cushman Collection, Smithsonian Institution, Washington, D.C., shows 21 chambers (Pl. 4, figs. 1-2). Elsewhere such specimens with numerous chambers and a more elongate appearance are rare, being reported only by Huber and others (1999) from the western North Atlantic (Blake Plateau, ODP Leg 171B). Most of the paratypes (USNM 307960-307962) display tests consisting of 17 to 19 chambers." [copied from Chronos database]

Type images:

holotype: G. moremani
holotype: G. moremani
holotype: G. moremani
holotype: G. moremani
holotype: G. moremani
paratype: G. moremani
paratype: G. moremani
paratype: G. moremani
paratype: G. moremani

Original description: Slender test with up to 18 chambers that subglobular to slightly reniform, or deeper than wide.--Huber "Test elongate, 2½-3 times as long as broad, gradually tapering throughout, only slightly enlarging in the later portion, periphery distinctly indented throughout; chambers globular, often slightly irregular and occasionally with one developed at the side in the adult; sutures distinct and depressed throughout; wall smooth, finely perforate; aperture, a high arched opening at the inner margin of the last-formed chamber, with a slight lip which may reach forward at the sides onto the previously formed chamber.

Entries in the Catalog of original descriptions: Guembelina moremani, Guembelina boliviniformis

Emended description:

Georgescu & Huber. 2009, p.81: "Test is slender and symmetrical in edge view. It consists of 14-21 chambers, which are biserially arranged throughout, subglobose in the juvenile portion, and elongate and oblique to the axis of growth in the adult stage. The proloculus (10.8-16.4 microns) is smaller than the second chamber. Sutures are distinct, straight and depressed, and oblique to the test axis of growth. Aperture is a medium-high arch at the base of the last-formed chamber. Two delicate, symmetrically developed periapertural flanges border the aperture. Chamber surface is smooth but aligned pustules and rarer incipient costae can be occasionally observed on the earlier part of the test. Test wall is calcitic, hyaline and microperforate; pore diameter ranges 0.5-0.7 microns." [copied from Chronos database]

Character matrix
test outline: Elongate chamber arrangement: Biserial edge view: Compressed aperture: Interiomarginal
sp chamber shape: Inflated coiling axis: N/A periphery: N/A aperture border: Thin flange
umb chbr shape: Inflated umbilicus: N/A periph margin shape: Broadly rounded accessory apertures: None
spiral sutures: Moderately depressed umb depth: N/A wall texture: Smooth shell porosity: Microperforate: <1µm
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

Geological Range:
Last occurrence (top): within H. helvetica zone (92.56-93.52Ma, top in Turonian stage). Data source: [copied from Chronos database]
First occurrence (base): within T. reicheli zone (95.94-96.08Ma, base in Cenomanian 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
Histogram - Neptune occurrence data from DSDP and ODP proceedings. Pale shading <50 samples in time bin. Interpret with caution & read these notes
Taxon plotted: Planoheterohelix moremani, synonyms included - Guembelina bolivinformis; Guembelina washitensis; Heterohelix boliviniformis; Heterohelix moremani; Heterohelix washitensis;
See also space-time plot :: Samples map :: Parent: Planoheterohelix

References:

Cushman, J. A. (1938). Cretaceous species of Guembelina and related genera. Contributions from the Cushman Laboratory for Foraminiferal Research. 14: 2-28. gs V O

Falzoni, F., Petrizzo, M. R., Jenkyns, H. C., Gale, A. S. & Tsikos, H. (2016). Planktonic foraminiferal biostratigraphy and assemblage composition across the Cenomanian–Turonian boundary interval at Clot Chevalier (Vocontian Basin, SE France). Cretaceous Research. 59: 69-97. gs

Nederbragt, A. J. (1991). Late Cretaceous biostratigraphy and development of Heterohelicidae (planktic foraminifera). Micropaleontology. 37: 329-372. gs

Pessagno, E. A. (1967). Upper Cretaceous planktonic foraminifera from the western Gulf Coastal Plain. Palaeontographica Americana. 5: 245-445. gs V O

Planoheterohelix moremani compiled by the pforams@mikrotax project team viewed: 2-4-2023

Taxon Search:

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AphiaID: 1034738 Nomenclatural data on WoRMS
Short stables page link: https://mikrotax.org/pforams/index.php?id=110402 Go to Archive.is to create a permanent copy of this page - citation notes

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test outline:	Elongate	chamber arrangement:	Biserial	edge view:	Compressed	aperture:	Interiomarginal
sp chamber shape:	Inflated	coiling axis:	N/A	periphery:	N/A	aperture border:	Thin flange
umb chbr shape:	Inflated	umbilicus:	N/A	periph margin shape:	Broadly rounded	accessory apertures:	None
spiral sutures:	Moderately depressed	umb depth:	N/A	wall texture:	Smooth	shell porosity:	Microperforate: <1µm
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