Taxonomy
Original description: Diagnosis: Trochospiral test with more convex umbilical side, with four chambers in the final whorl and strongly overlapping chambers. Periphery with one distinct keel. Sutures sigmoidal.
Description of the test: Trochospirally coiled test with four chambers in the final whorl. Chambers are strongly overlapping. The umbilical side of the test rather convex, the spiral one concave or flattened. Periphery with one distinct keel. The aperture interiomarginal, accessory apertures with lips at the adumbilical portions of the last chambers. Surface smooth.
Entries in the Catalog of original descriptions: Globotruncana sigmoconcavata
Geological Range:
Last occurrence (top): within Dicarinella asymetrica zone (83.65-85.60Ma, top in Santonian stage). Data source:
First occurrence (base): within Marginotruncana schneegansi zone (89.75-92.51Ma, base in Turonian stage). Data source:
Plot of range and occurrence data:
Missing or ambiguous references: Scheibnerova 1963 221-268; References:
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Marginotruncana sigmoconcavata compiled by the pforams@mikrotax project team viewed: 12-5-2025
Short stable page link: https://mikrotax.org/pforams/index.php?id=110587 Go to Archive.is to create a permanent copy of this page - citation notes |
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Comments (2)
Basionym: Globotruncana sigmoconcavata (Scheibnerova 1963) no brackets
sorry for my telegraphic style
thanks, good to correct these, i will check the database for any more. Jeremy