Original descriptions of taxa. For coccolithophores, and many calcispheres, these are pages from the Farinacci & Howe Catalog of Calcareous Nannofossils. In other cases (e.g. non-calcifying haptophytes) the data is directly compiled on this site. The "Catalogue of Calcareous Nannofossils" was originally compiled by Prof A. Farinacci 1969-1989, since 2000 it has been updated and extended by Richard Howe - see The Farinacci and Howe Catalog - an Introduction.
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Citation: Discoaster bordii Varol 2023Taxonomic rank: speciesType specimens: Plate 24, Figs. 1-12 [same specimen in mobile mount.]Type sample (& lithostrat): DSDP Leg 39, Site 354-16-1, 46 cm.Type age (chronostrat): Thanetian, Zone NP9Standardised type level: 093_UPPER PALEOCENEType locality: Ceara Rise, Atlantic OceanType repository: not stated, presumalby the author's collectionRepository Country: Wales, UK
Original Description Diagnosis: A large (8.0–13.0 μm) circular species of Discoaster with a non-birefringent lenticular disc and a solid non-birefringent, disjunct proximal structure.
Description: The number of segments that make up the disc is between 19 and 32 and are joined along most of their length. In side view, the relatively narrow proximal structure is often parallel-sided and has a slightly concave proximal end. Size: Dimensions of holotype: The diameter of the disc =12.11 μm, the
thickness of the disc =4.25 μm, the diameter of the proximal structure
=4.02 μm, the height of the proximal structure =2.31 μm; all measured
in phase-contrast. Etymology: In honour of nannofossil specialist Dr. D Bord, Ellington
Geological Services, Houston, Texas, USA. Extra details from original publication Remarks: Discoaster bordii is distinguished from Discoaster multiradiatus by having a solid, discrete proximal structure. Discoaster bordii differs from Candeodiscoaster protomultiradiatus in that it has a solid proximal structure and lacks tube cycle.
Occurrence: This species is recorded from DSDP Leg 39, Site 354, Ceara Rise, Atlantic Ocean; DSDP Leg 25, Site 245A, Mozambique Channel (Davie Ridge); DSDP Leg 25, Site 245A, Mozambique Channel (Davie Ridge), Indian Ocean; ODP Leg 171, Site 1051A, Blake Nose, western North Atlantic Ocean.
Stratigraphic range: Thanetian (Zone NP9).
References:
Varol, O. (2023). New Paleocene calcareous nannofossils: Carlamuelleria, Davidbukrya, Mauriceblackia, Noelia and Senelia. Marine Micropaleontology. 180: 1-41. gs