Nannotax3 - ntax_main - Reticulofenestra minutula

Citation: Reticulofenestra minutula (Gartner 1967) Haq & Berggren 1978

Basionym: Coccolithus minutulus * Gartner 1967

Taxonomic discussion: N.B. Coccolithus doronicoides Black and Barnes, 1961. According to Young (1998) "The holotype of this species is a proximal view TEM of a reticulofenestrid coccolith 3.4 µm long which might be either a Gephyrocapsa or Reticulofenestra, as it is not possible to tell if a bridge is present. Re-examination of the type material (HMS Challenger dredging 338) reveals that it contains an Holocene or Late Pleistocene assemblage, with minimal reworking. The assemblage contains abundant Gephyrocapsa oceanica but no true Reticulofenestra of this size. So Coccolithus doronicoides is best regarded as a junior synonym of G. oceanica Kamptner, 1943 and the name should certainly not be used for Neogene Reticulofenestra specimens."

Distinguishing features:
Parent taxon (R. pseudoumbilicus group): Neogene elliptical reticulofenestrids with an open central area (spanned by delicate proximal net, not visible in lm)
This taxon: Coccoliths small 3-5µm, without slits, intergrades with Pseudoemiliania lacunosa.

Intergrades with Pseudoemiliania ovata which is similar but has a few slits in the distal shield. Coccospheres containing examples of both "species" can occur. See also discussion in Young (1990).

Geological Range:
Last occurrence (top): within NN18 zone (1.93-2.39Ma, top in Gelasian stage). Data source: Young 1998
First occurrence (base): within NN15 zone (3.70-3.92Ma, base in Zanclean stage). Data source: Young 1998

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

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

Ghidalia, M. -J. (1988). Les Gephyrocapsaceae (Coccolithophoridées) des coupes de Stuni et de Vrica, Italie, stratotype de la limite Plio-Pléistocène. Étude systématique et intérêt stratigraphique. Cahiers de Micropaléontologie. 3(1): 5-49. gs O

Haq, B. U. & Berggren, W. A. (1978). Late Neogene calcareous plankton biochronology of the Rio Grande Rise (South Atlantic Ocean). Journal of Paleontology. 52: 1167-1194. gs

Jafar, S. A. (1975). Calcareous nannoplankton from the Miocene of Rotti, Indonesia. Verhandelingen der Koninklijke Nederlandse Akademie van Wetenschappen. 28: 1-99. gs O

Kamptner, E. (1956). Zur Systematik und Nomenklatur der Coccolithineen. Anzeiger der Österreichische Akademie der Wissenschaften, Wien. 93: 4-11. gs

Pujos, A. (1985). Cenozoic nannofossils, central equatorial Pacific, Deep Sea Drilling Project Leg 85. Initial Reports of the Deep Sea Drilling Project. 85: 581-607. gs

Samtleben, C. (1978). Pliocene-Pleistocene coccolith assemblages from Sierra Leone Rise - Site 366, Leg 41. Initial Reports of the Deep Sea Drilling Project. 41(16): 913-931. gs

Sato, T., Kameo, K. & Takayama, T. (1991). Coccolith biostratigraphy of the Arabian Sea. Proceedings of the Ocean Drilling Program, Scientific Results. 117: 37-54. gs

Young, J. R. (1990). Size variation of Neogene Reticulofenestra coccoliths from Indian Ocean DSDP cores. Journal of Micropalaeontology. 9: 71-86. gs

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

Reticulofenestra minutula

References:

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