Taxonomy
Original description: Test small, high spired. Both right- and left-coiling specimens occur. Height of coil variable. Spiral side usually convex, more rarely flat. Umbilical side concave. Contour of test lightly oval, lobate. Peripheral margin broad, rounded. Adult tests consist of 2.5-3 whorls. Total number of chambers 14-19, specimens with 17 chambers predominate. First whorl has 5-5.5 chambers, later whorls 6-7. Number of chambers per whorl increases each whorl by a half to one chamber. First 4-6 chambers spherical. Later chambers are trapezoidal on the spiral side, last 2-4 chambers are kidney-bean-shaped.
Entries in the Catalog of original descriptions: Hedbergella praetrocoidea
Emended description:
Character matrix
test outline: | Lobate | chamber arrangement: | Trochospiral | edge view: | Spiroconvex | aperture: | - |
sp chamber shape: | Globular | coiling axis: | Low | periphery: | N/A | aperture border: | Thin lip |
umb chbr shape: | Globular | umbilicus: | Narrow | 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: | 6-6.5 | 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: Banner et al., 1997
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-. gs Leckie, M. (1984). Mid-Cretaceous planktonic foraminiferal biostratigraphy off Central Morocco, Deep Sea Drilling Project Leg 79, Sites 545 and 547. Initial Reports of the Deep Sea Drilling Project. 79: 579-620. gs References:
Hedbergella praetrocoidea compiled by the pforams@mikrotax project team viewed: 8-12-2024
Short stable page link: https://mikrotax.org/pforams/index.php?id=110257 Go to Archive.is to create a permanent copy of this page - citation notes |
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Comments (3)
the photo DSDP Site 511-144.DSDP here, is equal of Huber and Leckie 2011_5-10-134JPG of Hedbergella infracretacea.
Thank you for pointing out this mistake!
We have now deleted the copy of the image which was here accidentally. It is almost inevitable that mistakes get onto the site so it is really useful when they are pointed out.
Jeremy