Calcidiscus leptoporus


Classification: Coccolithophores -> Coccolithales -> Calcidiscaceae -> Calcidiscus -> C. leptoporus group -> Calcidiscus leptoporus
Sister taxa: C. gallagheri, C. leptoporus, C. macintyrei, C. pataecus, C. premacintyrei, C. salomonii, C. tropicus,

Daughter taxa: (blue => in age window 0-800Ma)
liths 5-8µm, often weakly elliptical, sutures sharp around central area
liths 7-9µm, circular, sutures obscured around central area
liths <5µm, sutures often complex

Taxonomy:

Citation: Calcidiscus leptoporus (Murray & Blackman 1898) Loeblich & Tappan, 1978
Rank: Species
Basionym: Coccosphaera leptopora Murray & Blackman 1898
Variants:
Synonyms:
Notes & discussion: This is something of a default name applied to a wide range of morphotypes but in most Neogene assemblages there is clearly a separation between slightly sub-cicular forms with a closed central area (leptoporus) and circular froms with an open central area (tropicus). In the modern nannoflora C. leptoporus has often been subdivided into small (<5µm), intermedate (5-8µm), and large (>8µm) forms. The large forms are now distinguished as C. quadriperforatus.
This subdivision into three morphotypes or sub-species was first proposed by Kleijne (1993). It has been supported by extensive subsequent work on their biogeography, morphology, stability in culture, associated holococcoliths, and molecular genetics (Knappertsbusch 1997, Baumann & Sprengel 2000, Renaud & Klaas 2001, Renaud et al. 2002, Geisen et al. 2002, Sáez et al. 2004, Quinn et al 2004). We follow Geisen et al. (2002) in treating them as sub-species, but algologists often treat them as species, folowing Quinn et al. (2004).

Distinguishing features: Species of Calcidiscus producing circular to sub-circular coccoliths with, closed central-area.

Farinacci & Howe catalog pages: Coccosphaera leptopora * , Coccolithophora leptopora * , Calcidiscus medusoides * , Crepidolithus etruscus * , Cyclococcolithus leptoporus centrovalis * , Cycloplacolithus laevigatus * , Calcidiscus quadriforatus *

Search data:
TagsLITHS: placolith, circular, sub-circular, RIM: rim-broad, CA: Placoliths: closed,
CSPH: spherical, monomorphic, V-UNITS: distal shield, tube, R-UNITS: prox shield, DETAILS: isogyres oblique, rim-unicyclic,
MetricsLith size: 3->10µm; Coccosphere size: 5->20µm; Liths per sphere: 20->50
Sources: lith numbers from Yang & Wei 2003, range of estimates
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): Extant Data source: present in the plankton (Young et al. 2003)
First occurrence (base): within NN2 zone (19.00-22.82Ma, base in Aquitanian stage). Data source: Young (1998)

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: Calcidiscus leptoporus, synonyms included - Calcidiscus leptoporus; Calcidiscus leptoporus f. rigidus; Calcidiscus leptoporus hol; Calcidiscus leptoporus subsp. centrovalis; Calcidiscus quadriforatus; Coccosphaera leptopora; Cyclococcolithina leptopora; Cyclococcolithus leptoporus;
  • space-time plot :: Samples map :: Parent: C. leptoporus group

    References:

    Backman, J. (1980). Miocene-Pliocene nannofossils and sedimentation rates in the Hatton-Rockall Basin, NE Atlantic Ocean. Stockholm Contributions in Geology. 36: 1-91. gs

    Bartolini, C. & Pirini, C. (1969). Decouverte de nannoplancton calcaire dans les gres de Ponsano, Miocene Moyen, Toscane, Italie. In, Bronnimann, P. & Renz, H. H. (eds) Proceedings of the First International conference on Planktonic Microfossils, Geneva 1967. E. J. Brill, Leiden 81-88. gs

    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

    da Gama, R. O. B. P. & Varol, O. (2012). New Late Oligocene to Miocene Species. Journal of Nannoplankton Research. 33(1): 1-12. gs

    de Kaenel, E. & Villa, G. (1996). Oligocene-Miocene calcareous nannofossil biostratigraphy and paleoeecology from the Iberian Abyssal Plain. Proceedings of the Ocean Drilling Program. Scientific Results. 149: 79-145. gs

    Gartner, S. (1967b). Nannofossil species related to Cyclococcolithus leptoporus (Murray and Blackman). University of Kansas Paleontological Contributions. Paper 28: 1-4. gs

    Gartner, S. (1967a). Calcareous nannofossils from Neogene of Trinidad, Jamaica, and Gulf of Mexico. Paleontological Contributions. University of Kansas. 29: 1-7. gs

    Janin, M. -C. (1987). Micropaleontologie de concretions polymetalliques du Pacifique central: zone Clarion-Clipperton, chaine Centre-Pacifique, lles de la Ligne et archipel des Tuoamotou (Eocene-Actuel). Mémoires de la Société géologique de France. Paris. 152: 1-315. gs

    Müller, C. (1974c). Nannoplankton aus dem Mittel-Miozän von Walbersdorf (Burgenland). Senckenbergiana Lethaea. 55: 389-405. gs

    Murray, G. & Blackman, V. H. (1898). On the nature of the Coccospheres and Rhabdospheres. Philosophical Transactions of the Royal Society of London (B). 190(1): 427-441. gs

    Perch-Nielsen, K. (1972). Remarks on Late Cretaceous to Pleistocene coccoliths from the North Atlantic. Initial Reports of the Deep Sea Drilling Project. 12: 1003-1069. gs

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

    Wei, W. & Wise, S. W. (1990). Middle Eocene to Pleistocene calcareous nannofossils recovered by Ocean Drilling Program leg 113 in the Weddell Sea. Proceedings of the Ocean Drilling Program. Scientific Results. 113: 639-666. gs

    Wei, W. & Wise, S. W. (1992b). Selected Neogene calcareous nannofossil index taxa of the  from Southern Ocean: Biochronology, biometrics and paleoceanography. Proceedings of the Ocean Drilling Program. Scientific Results. 120: 523-537. gs

    Wise, S. W. & Wind, F. H. (1977). Mesozoic and Cenozoic calcareous nannofossils recovered by DSDP Leg 36 drilling on the Falkland Plateau, south-west Atlantic sector of the Southern Ocean. Initial Reports of the Deep Sea Drilling Project. 36(269-491): -. gs

    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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    Calcidiscus leptoporus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 18-11-2019

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    Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=179 Go to Archive.is to create a permanent copy of this page - citation notes



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