Nannotax3 - ntax_cenozoic - Umbilicosphaera protoannulus

Citation: Umbilicosphaera protoannulus (Gartner, 1971) Young & Bown 2014

Basionym: Cyclococcolithina protoannula Gartner, 1971

Synonyms:

Cyclococcolithus protoannulus (Gartner) Haq & Lohmann 1976
Calcidiscus protoannulus (Gartner, 1971) Loeblich & Tappan, 1978
Cyclolithella pakistanica Haq 1971 [my interpretation - JRY 2021 ih ave notchecked which name has priority but protoannulus has been used far more]

Taxonomic discussion: Transferred to Umbilicosphaera by Young & Bown (2014) since it has a wide central area (central area width >25% of distal shield width).

NB The epithet protoannulus is based on the Latin masculine noun annulus (ring). It thus does not change gender and the correct orthography is Umbilicosphaera protoannulus.

Distinguishing features:
Parent taxon (Umbilicosphaera): Central area open
This taxon: Small to medium sized (4.5-8.0 µm) ring-shaped coccoliths that are distinctly bicyclic in XPL: the bright inner cycle is narrower than the outer cycle, and crossed by extinction lines that are near axial.

Geological Range:
Last occurrence (top): within NP21 zone (32.92-34.44Ma, top in Rupelian stage). Data source: Bown et al., 2007
First occurrence (base): within NP11 zone (53.70-54.17Ma, base in Ypresian stage). Data source: Bown et al., 2007

References:

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 O

Bown, P. R. & Newsam, C. (2017). Calcareous nannofossils from the Eocene North Atlantic Ocean (IODP Expedition 342 Sites U1403–1411). Journal of Nannoplankton Research. 37(1): 25-60. gs O

Bown, P. R. (2005d). 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 O

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

Gartner, S. (1971). Calcareous nannofossils from the JOIDES Blake Plateau cores and revision of the Paleogene nannofossil zonation. Tulane Studies in Geology and Paleontology. 8: 101-121. gs O

Haq, B. U. & Lohmann, G. P. (1976). Early Cenozoic calcareous nannoplankton biogeography of the Atlantic Ocean. Marine Micropaleontology. 1: 119-194. gs

Jones, A. P. & Dunkley Jones, T. (2020). Middle Eocene to Early Oligocene calcareous nannofossils from the Nanggulan Formation, Java, Indonesia. Journal of Nannoplankton Research. 38(1): 57-79. gs

Loeblich, A. R. & Tappan, H. (1978). The coccolithophorid genus Calcidiscus Kamptner and its synonyms. Journal of Paleontology. 52: 1390-1392. gs

Müller, C. (1979). Calcareous nannofssils from the North Atlantic (Leg 48). Initial Reports of the Deep Sea Drilling Project. 48: 589-639. 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 O

Shamrock, J. L. & Watkins, D. K. (2012). Eocene calcareous nannofossil biostratigraphy and community structure from Exmouth Plateau, Eastern Indian Ocean (ODP Site 762). Stratigraphy. 9(1): 1-11. gs

Shepherd, C. L. & Kulhanek, D. K. (2016). Eocene nannofossil biostratigraphy of the mid-Waipara River section, Canterbury Basin, New Zealand. Journal of Nannoplankton Research. 36(1): 33-59. gs O

Young, J. R. & Bown, P. R. (2014). Some emendments to calcareous nannoplankton taxonomy. Journal of Nannoplankton Research. 33(1): 39-46. gs

Umbilicosphaera protoannulus

References:

Add Comment

Comments