Stephanolithion speciosum


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

Distinguishing features: Elliptical Stephanolithion with multiple short rim spines and central area spanned by eight cross bars.


Taxonomy:

Citation: Stephanolithion speciosum Deflandre in Deflandre & Fert, 1954
Rank: Species
Variants: Stephanolithion speciosum Deflandre in Deflandre & Fert, 1954 ssp. octum Rood & Barnard, 1972 = Stephanolithion octum (Rood & Barnard, 1972) Perch-Nielsen, 1984. Variant with 8-12 long rim spines - there appears to be relatively continuous variation in the length of the rim spines and so this morphotype should probably be considered a variant of Stephanolithion speciosum.
Stephanolithion carinatum Medd 1979 - smaller (holotype sizes 3.3 x 2.5 µm vs 5.8 x 4 µm)

Farinacci & Howe catalog pages: Stephanolithion speciosum * , Stephanolithion speciosum octum * , Stephanolithion carinatum * ,

Distinguishing features: Elliptical Stephanolithion with multiple short rim spines and central area spanned by eight cross bars.


Morphology remarks: There appears to be relatively continuous variation in the length of the rim spines and so the species/subspecies Stephanolithion speciosum octum (distinguished by longer rim spines) should probably be considered a subspecies or variant of Stephanolithion speciosum.

Geological Range:
Last occurrence (top): within NJ12b subzone (164.79-165.55Ma, top in Callovian stage). Data source: Bown & Cooper 1998
First occurrence (base): at base of NJ10 zone (0% up, 169.7Ma, in Bajocian 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:

    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

    Deflandre, G. & Fert, C. (1954). Observations sur les coccolithophoridés actuels et fossiles en microscopie ordinaire et électronique. Annales de Paléontologie. 40: 115-176. gs

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

    Perch-Nielsen, K. (1984). Validation of new combinations. INA Newsletter. 6(1): 42-46. gs

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


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    Stephanolithion speciosum compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 20-7-2019

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    Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=11155 Go to Archive.is to create a permanent copy of this page - citation notes



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