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Blefuscuiana implana


Classification: pf_mesozoic -> Praehedbergellidae -> Blefuscuiana -> Blefuscuiana implana
Sister taxa: B. alobata, B. cumulus, B. daminiae, B. depressa, B. implana, B. laculata,

Taxonomy

Citation: Blefuscuiana implana (Banner, Copestake & White, 1993)
Rank: Species
Basionym: Blefuscuiana aptiana implana implana

Type images:

Original description: Blefuscuiana aptiana implana implana Banner, Copestake & White 1993: Test about 0.15-0.2mm at its maximum diameter, comprising about 2-3 whorls coiled in a low trochospire. There are 5-6 chambers in each of the penultimate and last whorls. The spiral side is almost flat or slightly convex and the intercameral sutures are moderately depressed, forming angles of about 130-140 degrees at the periphery of the test. The chambers are symmetrical and increase in size gradually with growth, they are typically subglobular to slightly depressed (about 7) as high as long when viewed from the spiral side) in the last whorl, although in some the first 1-2 chambers in the last whorl may be more strongly depressed (about half as high as long). The umbilicus is broadly open and the aperture is a narrow slit. Perforation cones are present on chambers of the last whorl.

Entries in the Catalog of original descriptions: Blefuscuiana aptiana implana implana;

Geological Range:
Last occurrence (top): within Aptian Stage (112.95-126.30Ma, top in Aptian stage). Data source: [copied from Chronos database]
First occurrence (base): within Barremian Stage (126.30-130.77Ma, base in Barremian stage). Data source: [copied from Chronos database]

Plot of occurrence data:

NB Plotting of Neptune data has been disabled on the Mesozoic pages because the dataset is both small and badly affected by a few sites with erroneous age models (our obs Huber, Petrizzo, Young, Nov 2016). The data can still be viewed via the range plottertool - tools menu.

Character matrix

test outline:coiling axis:Lowchamber arrangement:Trochospiralumbilicus:Wide
edge view:umbilical or test sutures:spiral sutures:Moderately depressedshell porosity:
wall texture:aperture:aperture border:accessory apertures:
periphery:umb chamber shape:sp chbr shape:periph margin shape:
umb depth:Shallowdiameter mm:width mm:breadth mm:
final-whorl chambers:5.0-6.0

References:

Banner, F.T.; Copestake, P. & White, M.R., (1993). Barremian-Aptian Praehedbergellidae of the North Sea area: a reconnaisance. Bulletin of the Natural History Museum, London (Geology), 49: 1-30.


Blefuscuiana implana compiled by the pforams@mikrotax project team viewed: 23-5-2017

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