Taxonomy
Original description: 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
Character matrix
test outline: | - | chamber arrangement: | Trochospiral | edge view: | - | aperture: | - |
sp chamber shape: | - | coiling axis: | Low | periphery: | - | aperture border: | - |
umb chbr shape: | - | umbilicus: | Wide | periph margin shape: | - | accessory apertures: | - |
spiral sutures: | Moderately depressed | umb depth: | Shallow | wall texture: | - | shell porosity: | - |
umbilical or test sutures: | - | final-whorl chambers: | 5-6 | 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 Barremian Stage (121.40-126.50Ma, base in Barremian 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 implana compiled by the pforams@mikrotax project team viewed: 10-12-2024
Short stable page link: https://mikrotax.org/pforams/index.php?id=110029 Go to Archive.is to create a permanent copy of this page - citation notes |
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