Taxonomy
Original description: Characterised by its high spired test, with its very convex dorsal surface, and by having 5 chambers in the last whorl. Test about 0.20mm at its maximum diameter, comprising about 2-3 whorls coiled in high trochospire. There are about 5 chambers in each of the penultimate and last whorls. The spiral side is strongly convex, and the intercameral sutures are moderately depressed, forming angles of about 135-140 degrees at the periphery of the test. The chambers are symetrical and increase in size gradually with growth, becoming depressed, being about half as high as long in the last whorl (when viewed from the spiral side). The umbilicus is small and deep, and the aperture is probably a narrow slit. Perforation-cones have not been found on this species.
Entries in the Catalog of original descriptions: Blefuscuiana excelsa cumulus
Character matrix
test outline: | chamber arrangement: | Trochospiral | edge view: | aperture: | |||
sp chamber shape: | coiling axis: | High | periphery: | aperture border: | |||
umb chbr shape: | umbilicus: | Narrow | periph margin shape: | Moderately rounded | accessory apertures: | ||
spiral sutures: | Moderately depressed | umb depth: | Deep | wall texture: | shell porosity: | ||
umbilical or test sutures: | Moderately depressed | final-whorl chambers: | 5-5 | N.B. These characters are used for advanced search. N/A - not applicable |
Geological Range:
Last occurrence (top): within Aptian Stage (113.20-121.40Ma, top in Aptian stage). Data source: [copied from Chronos database]
First occurrence (base): within Aptian Stage (113.20-121.40Ma, base in Aptian stage). Data source: [copied from Chronos database]
Plot of range and occurrence data:
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. gsReferences:
Blefuscuiana cumulus compiled by the pforams@mikrotax project team viewed: 15-9-2024
Short stable page link: https://mikrotax.org/pforams/index.php?id=110026 Go to Archive.is to create a permanent copy of this page - citation notes |
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