Stephanolithion bigotii


Classification: Mesozoic -> Stephanolithiales -> Stephanolithiaceae -> Stephanolithion -> Stephanolithion bigotii
Sister taxa: S. atmetos, S. bigotii, S. brevispinus, S. hexum, S. speciosum, S. sp.,

Distinguishing features: Broadly elliptical or hexagonal Stephanolithion with long rim spines and central area spanned by diagonal cross bars.


Daughter taxa: (blue => in age window 0-800Ma)
Polygonal Stephanolithion (elongated hexagon) with six (sometimes 7-8) long rim spines and central area spanned by diagonal cross bars.
Large, elliptical Stephanolithion with multiple rim spines and wide central area spanned by diagonal cross bars

Taxonomy:

Citation: Stephanolithion bigotii Deflandre, 1939
Rank: Species
Basionym: Stephanolithion bigoti Deflandre, 1939
Synonyms:
Notes & discussion: Smaller forms are typically hexagonal with six spnes, one at each corner of the rim. Larger forms are more elliptical and may have additonal spnes. Medd (1979) separated the species into two sub-species S. bigotii maxima and S. bigotii bigotii based on size alone. However, many workers use other criteria for separating these two sub-species. At the Jurassic workshop in Lyon 2016, it was suggested that the most objective criterion was presence of additional spines - with S. bigotii bigotii being confined to specimens with spines only at the corners of the hexagonal rim.

Farinacci & Howe catalog pages: Stephanolithion bigoti * , Stephanolithion laffittei *

Distinguishing features: Broadly elliptical or hexagonal Stephanolithion with long rim spines and central area spanned by diagonal cross bars.

Geological Range:
Last occurrence (top): at top of NJ17a subzone (100% up, 149.1Ma, in Tithonian stage). Data source: Bown & Cooper 1998 (fig 4) - zonal eventBown & Cooper 1998
First occurrence (base): at base of NJ13 zone (0% up, 164.8Ma, in Callovian stage). Data source: Bown & Cooper 1998 (fig 4) - zonal event

Plot of occurrence data:

  • (NB There is no histogram as there are no occurrence records for the taxon in the Neptune database) Parent: Stephanolithion

    References:

    Barnard, T. & Hay, W. W. (1974). On Jurassic coccoliths: A tentative zonation of the Jurassic of Southern England and North France. Eclogae Geologicae Helvetiae. 67(3): 563-585. 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

    de Kaenel, E. & Bergen, J. A. (1996). Mesozoic calcareous nannofossil biostratigraphy from sites 897, 899, and 901, Iberia Abyssal Plain: New biostratigraphic evidence. Proceedings of the Ocean Drilling Program. Scientific Results. 149: 27-59. gs

    Deflandre, G. (1939). Les stéphanolithes, représentants d'un type nouveau de coccolithes Jurassique supérieur. Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences. Paris. 208: 1331-1333. gs

    Grün, W. & Zweili, F. (1980). Das kalkige Nannoplankton der Dogger-Malm-Grenze im Berner Jura bei Liesberg (Schweiz). Jahrbuch der Geologischen Bundesanstalt. 123: 231-341. gs

    Medd, A. W. (1979). The Upper Jurassic coccoliths from the Haddenham and Gamlingay boreholes (Cambridgeshire, England). Eclogae Geologicae Helvetiae. 72: 19-109. gs

    Noël, D. (1973). Nannofossiles calcaires de sédiments jurassiques finement laminés. Bulletin du Muséum National d'Histoire Naturelle. 3e serie, 75: 95-156. gs

    Rood, A. P. & Barnard, T. (1972). On Jurassic coccoliths: Stephanolithion, Diadozygus and related genera. Eclogae Geologicae Helvetiae. 65: 327-342. gs

    Rood, A. P., Hay, W. W. & Barnard, T. (1971). Electron Microscope Studies of Oxford Clay Coccoliths. Eclogae Geologicae Helvetiae. 64: 245-272. gs

    Wise, S. W. (1983). Mesozoic and Cenozoic calcareous nannofossils recovered by DSDP Leg 71 in the Falkland Plateau region, Southwest Atlantic Ocean. Initial Reports of the Deep Sea Drilling Project. 71: 481-550. gs


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    Stephanolithion bigotii compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 13-11-2019

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    Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=11148 Go to Archive.is to create a permanent copy of this page - citation notes



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