Rhabdosphaera clavigera


Classification: Coccolithophores -> Syracosphaerales -> Rhabdosphaeraceae -> Rhabdosphaera -> Rhabdosphaera clavigera
Sister taxa: R. clavigera, R. gracilenta, R. poculii, R. vitrea, R. xiphos, R. sp.,

Daughter taxa: (blue => in age window 0-800Ma)
Spine with pentameral structure - robust, club-shaped, 7-10µm long
Spine with pentameral structure - narrow, parallel-sided, 3-5µm long

Taxonomy:

Citation: Rhabdosphaera clavigera Murray & Blackman, 1898
Rank: Species
Basionym: Rhabdosphaera claviger Murray & Blackman, 1898
Variants:
Synonyms:
Notes & discussion: Forms with club-shaped (clavigera) and narrower parallel-sided (stylifera) spines are often separated as varieties of R. clavigera. However the two types intergrade and both can be found on single coccospheres, suggesting this is an example of degree of calcification variation rather than genotypic variation. Conversely, Kahn & Aubry (2006) provided strong evidence that the clavigera and stylifera morphotypes can form discrete populations, with clavigera being larger as well as more robust - spine lenth 7-9µm vs. 3-5µm. They concluded that they should be regarded as separate species. This division often works and smaller specimens do tend to have more delicate spines - but intermediates also occur, so retaining the taxa as varieties seems sensible.
In the plankton the stylifera variety is dominant but in the fossil record the clavigera variety is more commonly preserved.

Distinguishing features: Spine with pentameral structure

Farinacci & Howe catalog pages: Rhabdosphaera claviger * , Rhabdosphaera procera + * , Rhabdolithus siccus * , Discolithus phaseolus * , Discolithus pirenus * , Clavosphaera furonculata * , Rhabdosphaera murrayi * , Rhabdosphaera tignifer * , Rhabdosphaera otwayensis *


Morphology remarks:
Coccosphere: Spherical, usually non-motile but occasionally with flagella (Lohmann 1902, Probert unpubl.). Dimorphic with spine-bearing and spine-less coccoliths.
Coccoliths: Spines robust, formed of five clockwise-spiral sets of elements with pentameral terminal papilla. Base of coccoiths elliptical/oblong, 3-3.5 µm. Spine-bearing liths with wider rim than non spine-bearing liths.
In LM core of spine appears to be hollow, coccolith base is often missing but spine form is very characteristic.

Search data:
TagsLITHS: planolith, elliptical, sub-circular, PROCESS: length-slow, parallel-sided, spine,
CSPH: spherical, BC+process, BC-dimorphic, polymorphic, R-UNITS: spine, DETAILS: ca_disjunct,
MetricsLith size: 3->10µm; Coccosphere size: 20->35µm; Liths per sphere: 30->40
Sources: lith length from Kahn & Aubry 2006; csph size from illustrated specs; 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:
Notes: Common in the Late Miocene and Pliocene rather rarely recorded in older sediments. Dunkley jones et al. 2009 illustrated a rhabdosphaera spine with the classic R. clavigera structure from sediments of NP19-20 age
Last occurrence (top): Extant Data source: present in the plankton (Young et al. 2003)
First occurrence (base): within NN4 zone (14.91-17.95Ma, base in Burdigalian 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: Rhabdosphaera clavigera, synonyms included - Rhabdolithus claviger; Rhabdosphaera claviger; Rhabdosphaera clavigera; Rhabdosphaera procera; Rhabdosphaera sicca; space-time plot :: Samples map :: Parent: Rhabdosphaera

    References:

    Black, M. & Barnes, B. (1961). Coccoliths and discoasters from the floor of the South Atlantic Ocean. Journal of the Royal Microscopical Society. 80: 137-147. 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

    Fuchs, R. & Stradner, H. (1977). Uber Nannofossilien im Badenien (Mittelmiozan) der zentralen Paratethys. Beiträge zur Paläontologie von Österreichs. 2: 1-58. gs

    Kahn, A. & Aubry, M. -P. (2006). Intraspecific morphotypic variability in the Family Rhabdosphaeraceae. Micropaleontology. 52(4): 317-342. gs

    Kamptner, E. (1967). Kalkflagellaten - Skelettreste aus Tiefseeschlamm des Südatlantischen Ozeans. Annalen des Naturhistorischen Museums in Wien. 71: 117-198. gs

    Martini, E. (1969c). Nannoplankton aus dem Miozän von Gabon (Westafrika). Neues Jahrbuch für Geologie und Paläontologie Abhandlungen. 132: 283-300. 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

    Rade, J. (1977). Tertiary biostratigraohic zonation based on calcareous nannoplankton in eastrn Australian nearshore basins. Micropaleontology. 23(3): 270-296. gs

    Stradner, H. (1963). New contributions to Mesozoic stratigraphy by means of nannofossils. Proceedings of the Sixth World Petroleum Congress. Section 1 Paper 4: 167-183. 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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    Rhabdosphaera clavigera compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 20-9-2019

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    Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=1193 Go to Archive.is to create a permanent copy of this page - citation notes



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