Taxonomy
Original description: Test very small (major diameter up to 0.17 mm), low-spired. Spiral side of test flat, umbilical side concave. Outline rounded. Test consists of approximately 2 whorls, containing 11-13 chambers. In the first whorl are 5 chambers, in the second 5.5-6. Number of chambers in last whorl also fluctuates between 5.5 and 6. All chambers are spherical. Chambers gradually increase in size as added. Test surface smooth. Septal sutures linear, depressed, straight. Umbilicus broad, deep, aperture equatorial, lips not observed.
Entries in the Catalog of original descriptions: Clavihedbergella primare
Emended description:
Character matrix
test outline: | Circular | chamber arrangement: | Trochospiral | edge view: | Spiroconvex | aperture: | |
sp chamber shape: | Globular | coiling axis: | Very low | periphery: | N/A | aperture border: | Thin lip |
umb chbr shape: | Globular | umbilicus: | Wide | periph margin shape: | Broadly rounded | accessory apertures: | N/A |
spiral sutures: | Moderately depressed | umb depth: | Shallow | wall texture: | Smooth | shell porosity: | Finely Perforate: 1-2.5µm |
umbilical or test sutures: | Moderately depressed | final-whorl chambers: | 6-7 | N.B. These characters are used for advanced search. N/A - not applicable |
Geological Range:
Last occurrence (top): within G. algerianus zone (116.86-118.24Ma, top in Aptian stage). Data source: [copied from Chronos database]
First occurrence (base): within G. blowi zone (120.55-124.40Ma, base in Barremian stage). Data source: [copied from Chronos database]
Plot of range and occurrence data:
Gorbachik, T. N. (1986). Jurassic and early Cretaceous planktonic foraminifera of the south of the USSR. Moscow: Izdat. “Nauka”. 1986: 120-. gsReferences:
Hedbergella primare compiled by the pforams@mikrotax project team viewed: 14-12-2024
Short stable page link: https://mikrotax.org/pforams/index.php?id=110258 Go to Archive.is to create a permanent copy of this page - citation notes |
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