Watznaueria


Classification: Mesozoic -> Watznaueriales -> Watznaueriaceae -> Watznaueria
Sister taxa: Bussonius, Cyclagelosphaera, Diazomatolithus, Lotharingius, Watznaueria, Ansulasphaera, Bibreviconus, Perchnielsenella,

Distinguishing features: Elliptical watznaueriacean coccoliths with central-areas that are typically closed or narrow but may be spanned by transverse bar, bars or grill.  Extinction figure with clearly inflected arms.


Daughter taxa: (blue => in age window 0-800Ma) Granddaughter taxa
Species without central structure
Central-area closed or very narrow, with no central area structures.

Watznaueria-like in appearance but appear flat and have relatively large, visible rim elements.

Watznaueria with a narrow central-area opening with no central area structures.

Large (>9µm) Watznaueria with central-area that is closed or with only very narrow opening, with no central area structures.

Watznaueria with a wide, vacant central area; c. area width >= rim width.

Species with disjunct bar
Watznaueria with narrow central-area spanned by a transverse bar.

Watznaueria with wide central-area spanned by a slightly oblique, narrow transverse bar that broadens at both ends.

Species with conjunct bar

Large Watznaueria with two well-defined pores separated by a conjunct transverse bar.



Broadly elliptical with two variably developed central pores that pierce the inner cycle.

Species with axial cross
Medium to large, broadly elliptical Watznaueria with narrow central area almost filled with axial cross bars.

Watznaueria species with sub-axial cross in the central area, long axis crossbar sigmoidal.

Small-medium sized Watznaueria with narrow central area spanned by axial cross bars.

Species with grill
Small to medium Watznaueria with relatively wide central-area spanned by around 5 parallel transverse bars.

Small-medium sized (4-6µm) Watznaueria with relatively wide central area (approximately the same width as the rim) spanned by an irregular grill of blocky laths. In LM the grill is impercetible or weakly birefringent.



Watznaueria with broad central-area spanned by radial bars

Specimens not identified to species level

Taxonomy:

Citation: Watznaueria Reinhardt, 1964
Rank: Genus
Type species: Tremalithus barnesae Black, 1959 (= the junior synonym of Watznaueria angustoralis Reinhardt, 1964, the original designation) designated by Perch-Nielsen, 1968.
Variants:
Synonyms:

Farinacci & Howe catalog pages: Watznaueria * , Ellipsagelosphaera * , Actinosphaera * , Caterella * , Calolithus * , Coptolithus * , Colvillea * , Maslovella * , Margolatus * ,

Distinguishing features: Elliptical watznaueriacean coccoliths with central-areas that are typically closed or narrow but may be spanned by transverse bar, bars or grill.  Extinction figure with clearly inflected arms.


Morphology remarks: The generic concepts applied to these kinds of coccoliths have been rather inconsistently applied with different kinds of central area bars used as diagnostic characters (e.g., Ellipsagelosphaera for forms with transverse bars). Here we use Watznaueria in a broad sense, but retain Lotharingius for the oldest, early Jurassic, representatives, and Cyclagelosphaera for circular forms.

Geological Range:
Last occurrence (top): at top of Maastrichtian Stage (100% up, 66Ma, in Maastrichtian stage). Data source: Total of range of species in this database
First occurrence (base): in upper part of Aalenian Stage (62% up, 171.8Ma, in Aalenian stage). Data source: Total of range of species in this database

Plot of occurrence data:

References:

Black, M. (1971a). Coccoliths of the Speeton Clay and Sutterby Marl. Proceedings of the Yorkshire Geological Society. 38: 381-424. gs

Black, M. (1973). British Lower Cretaceous Coccoliths. I-Gault Clay (Part 2). Palaeontographical Society Monograph. 127: 49-112. gs

Bown, P. R. & Cooper, M. K. E. (1998). Jurassic. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 34-85. gs

Burnett, J. A. (1998). Upper Cretaceous. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 132-199. gs

Noël, D. (1965). Sur les Coccolithes du Jurassique Européen et d'Afrique du Nord. Éditions du Centre National de la Recherche Scientifique, Paris. -. gs

Reinhardt, P. (1964). Einige Kalkflagellaten-Gattungen (Coccolithophoriden, Coccolithineen) aus dem Mesozoikum Deutschlands. Monatsberichte der Deutschen Akademie der Wissenschaften zu Berlin. 6: 749-759. gs


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Watznaueria compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 17-7-2019

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Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=11298 Go to Archive.is to create a permanent copy of this page - citation notes



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