Sphenolithus conicus


Classification: Coccolithophores -> Discoasterales -> Sphenolithaceae -> Sphenolithus -> S. heteromorphus group -> Sphenolithus conicus
Sister taxa: S. heteromorphus, S. milanetti, S. preasii, S. belemnos, S. pseudoheteromorphus, S. conicus, S. calyculus, S. delphix, S. microdelphix, S. spinula,

Taxonomy:

Citation: Sphenolithus conicus Bukry, 1971
Rank: Species

Distinguishing features: Large, coarsely constructed with high, gently tapering base and short tapering spine that is dark at 0° and bright at 45°.

Farinacci & Howe catalog pages: Sphenolithus conicus *


Morphology remarks: Similar to S. moriformis but with a small apical spine.
Also similar to S. heteromorphus but spine smaller. 


Size: Length given as 7-12 µm in the original descrition but this seems exagerrated and similar problems affect other species described in the same publication. Size range of 5-10 µm is generally seen. Bergen et al. (2017) suggest it ranges down to 4.5µm, but that larger specimens are more distinctive.

Search data:
TagsLITHS: nannolith-radiate, N: 3D-radiate, conical, circular, cylindrical, RIM: tiered, CA: process,
CSPH: not known, V-UNITS: spine, R-UNITS: all, lower-tier, middle-tier, R-prominent, DETAILS: isogyres radial,
MetricsLith size: 5->10µm;
Sources: lith height from illustrated specs
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: Bergen et al. 2017 record large forms (>7 µm) as having a shorter range than smaller ones - with LAD at the end of NN2.
Last occurrence (top): within NN3 zone (17.95-19.00Ma, top in Burdigalian stage). Data source: Bergen et al. 2017
First occurrence (base): within NP24 zone (26.84-29.62Ma, base in Rupelian stage). Data source: Bergen et al. 2017

Plot of occurrence data:

  • Histogram - Neptune occurrence data from DSDP and ODP proceedings. Pale shading <50 samples in time bin. Interpret with caution & read these notes
  • Note to users in China - the diagram may not plot unless you use a VPN since I use google services on the website. If this is a problem please contact me 谢谢.
  • Taxon plotted: Sphenolithus conicus, synonyms included - Sphenolithus conicus;
  • space-time plot :: Samples map :: Parent: S. heteromorphus group

    References:

    Bergen, J. A., de Kaenel, E., Blair, S. A., Boesiger, T. M. & Browning, E. (2017). Oligocene-Pliocene taxonomy and stratigraphy of the genus Sphenolithus in the circum North Atlantic Basin: Gulf of Mexico and ODP Leg 154. Journal of Nannoplankton Research. 37(2-3): 77-112. gs :: view :: open

    Bown, P. R. & Dunkley Jones, T. (2012). Calcareous nannofossils from the Paleogene equatorial Pacific (IODP Expedition 320 Sites U1331-1334). Journal of Nannoplankton Research. 32(2): 3-51. gs :: view :: open

    Bown, P. R. (2005). Palaeogene calcareous nannofossils from the Kilwa and Lindi areas of coastal Tanzania (Tanzania Drilling Project 2003-4). Journal of Nannoplankton Research. 27(1): 21-95. gs :: view :: open

    Bukry, D. (1971). Cenozoic calcareous nannofossils from the Pacific Ocean. San Diego Society of Natural History Transactions. 16: 303-327. gs :: ::

    Dunkley Jones, T., Bown, P. R. & Pearson, P. (2009). Exceptionally well preserved upper Eocene to lower Oligocene calcareous nannofossils (Prymnesiophycidae) from the Pande Formation (Kilwa Group), Tanzania. Journal of Systematic Palaeontology. 7(4): 359-411. gs :: ::

    Maiorano, P. & Monechi, S. (1998). Revised correlations of early and middle Miocene calcareous nannofossil events and magnetostratigraphy from DSDP Site 563 (North Atlantic Ocean). Marine Micropaleontology. 35(235-255): -. gs :: ::

    Perch-Nielsen, K. (1977). Albian to Pleistocene calcareous nannofossils from the Western South Atlantic, DSDP Leg 39. Initial Reports of the Deep Sea Drilling Project. 39: 699-823. gs :: view :: open

    Young, J. R. (1998). Neogene. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 225-265. gs :: ::


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    Sphenolithus conicus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 15-7-2020

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    Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=1291 Go to Archive.is to create a permanent copy of this page - citation notes



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