Nannotax3 - ntax_cenozoic - Triquetrorhabdulus milowii

Triquetrorhabdulus milowii

Classification: ntax_cenozoic -> Nannolith families inc sed -> Ceratolithaceae -> Triquetrorhabdulus -> Triquetrorhabdulus milowii
Sister taxa: T. carinatus, T. challengeri, T. longus, T. milowii, T. sp.


Citation: Triquetrorhabdulus milowii Bukry, 1971
Rank: Species
Variants: T. auritus Stradner and Allram, 1982 - more wedge-shaped, occasionally with ridges at blunt end.

Distinguishing features:
Parent taxon (Triquetrorhabdulus): Elongate, tri-radiate nannoliths formed of a single calcite crystal with the c-axis parallel to the length of the nannolith. Nannolith straight with bilateral or trilateral symmetry. Shows high birefringence.
This taxon: Short (8-15µm), broad (5-8µm) species of Triquetrorhabdulus with curved sides. All blades similar.

Farinacci & Howe catalog pages: T. milowii * , T. auritus *

Search data:
TagsLITHS: nannolith-other, rod-shaped, CROSS-POLARS: 1ou, R-prominent,
MetricsLith size: 8->15µm; Segments: 3->3;
Data source notes: lith length from illustrated specimens
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): within NN6 zone (11.90-13.53Ma, top in Serravallian stage). Data source: Young 1998
First occurrence (base): within NN1 zone (22.82-23.13Ma, base in Chattian stage). Data source: Young 1998

Plot of occurrence data:


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 V O

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

Perch-Nielsen, K. (1977a). 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 V O

Stradner, H. & Allram, F. (1982b). The nannofossil assemblages of Deep Sea Drilling Project Leg 66, Middle America trench. Initial Reports of the Deep Sea Drilling Project. 66: 589-639. gs V O

Theodoridis, S. (1984). Calcareous nannofossil biostratigraphy of the Miocene and revision of the helicoliths and discoasters. Utrecht Micropaleontological Bulletin. 32: 1-271. gs V O

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


Triquetrorhabdulus milowii compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 24-9-2021

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