Distinguishing features:
Parent taxon (Watznaueriaceae): Placoliths or modified placoliths with R-unit well developed, forming proximal and distal shield elements with opposite senses of imbrication; the V-unit typically forms a narrow distal cycle near the inner edge of the shield. Central-area structures are typically disjunct. Birefringent LM image, in which the V-unit cycle appears only as a thin, dark line.
This taxon: Elliptical watznaueriacean coccoliths with broad V-unit cycle, which results in a three tiered placolith structure. Moderately birefringent in XPL.
Daughter taxa (time control age-window is: 0-800Ma) | ||||
Bussonius fecheri Small (4-5µm) Bussonius with narrow shields and wide central area; distal shield closely appressed to proximal, 2-3 radial bars per quadrant. | ||||
Bussonius prinsii Small (4-6µm) Bussonius with narrow shields and wide central area; distal shield elevated, 3-4 radial bars per quadrant. | ||||
Bussonius leufuensis Medium-sized (6-7 µm) Bussonius with broad shields and relatively narrow central area. | ||||
Bussonius sp. Specimens not identified to species level |
Taxonomy:
Farinacci & Howe catalog pages: Bussonius *
Distinguishing features:
Parent taxon (Watznaueriaceae): Placoliths or modified placoliths with R-unit well developed, forming proximal and distal shield elements with opposite senses of imbrication; the V-unit typically forms a narrow distal cycle near the inner edge of the shield. Central-area structures are typically disjunct. Birefringent LM image, in which the V-unit cycle appears only as a thin, dark line.
This taxon: Elliptical watznaueriacean coccoliths with broad V-unit cycle, which results in a three tiered placolith structure. Moderately birefringent in XPL.
Search data:
LITHS: placolith, elliptical, CA: cross-axial, ca_disjunct, grill, process, CROSS-POLARS: rim-bicyclic, V-prominent, R-prominent, |
Lith size: 4->7µm; Data source notes: size range of included species |
Geological Range:
Last occurrence (top): at top of NJ8b subzone (100% up, 172.3Ma, in Aalenian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within Pliensbachian Stage (184.20-192.90Ma, base in Pliensbachian stage). Data source: Total of ranges of species in this database
Plot of occurrence data:
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 O Bown, P. R. & Young, J. R. (1997). Mesozoic calcareous nannoplankton classification. Journal of Nannoplankton Research. 19(1): 21-36. gs Goy, G., Noël, D. & Busson, G. (1979). Les conditions de sédimentation des schistes-carton (Toarcien inf.) du bassin de Paris déduites de l'étude des nannofossiles calcaires et des diagraphies. Document des Laboratoires de Géologie de la Faculté des Sciences de Lyon. 75: 33-57. gs OReferences:
Bussonius compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 11-9-2024
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=10145 Go to Archive.is to create a permanent copy of this page - citation notes |
This policy contains information about your privacy. By posting, you are declaring that you understand this policy:
This policy is subject to change at any time and without notice.
These terms and conditions contain rules about posting comments. By submitting a comment, you are declaring that you agree with these rules:
Failure to comply with these rules may result in being banned from submitting further comments.
These terms and conditions are subject to change at any time and without notice.
Comments