Olladiscoaster bordii

Varol & Bowman, 2024 Jan 29, 2025

Set number: 2482

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10µm

Olladiscoaster bordii, Middle Miocene, USGS-NASA Langley Core, Hampton, VA (USA)

In the mobile mount.

Set number: 2483

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10µm

Olladiscoaster bordii, Middle Miocene, USGS-NASA Langley Core, Hampton, VA (USA)

In the mobile mount.

Set number: 2484

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10µm

Olladiscoaster bordii, Middle Miocene, USGS-NASA Langley Core, Hampton, VA (USA)

Holotype in the mobile mount.

Set number: 2485

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10µm

Olladiscoaster bordii, Middle Miocene, USGS-NASA Langley Core, Hampton, VA (USA)

In the mobile mount.

Final Epithet

Olladiscoaster bordii Varol & Bowman, 2024

Basionym

Olladiscoaster bordii Varol & Bowman, 2024

Diagnosis

Circular to hexagonal species of Olladiscoaster have segments without arms. On the distal side, the distinct sutural ridges are created by the deep cavities. The sutural ridges are raised towards the centre and capped by kite-shaped distal covers. The distinct proximal ridges with a petaloid knob at the centre decorate the bulged proximal side. In the side view, Olladiscoaster bordii resembles a bouquet.

Etymology

In honour of Dr. David Bord, nannofossil specialist, Ellington Geological Services, Houston, Texas, USA.

Dimensions Of Holotype

Maximum diameter: 5.75 µm, Maximum height: 4.37 µm; Diameter of the proximal knob: 3.76 µm, Height of the proximal knob: 1.08 µm (measurements from bright field micrograph).

Remarks

Olladiscoaster bordii differs from Olladiscoaster cruzii, Olladiscoaster catinatus and Olladiscoaster asterilithos by having a kite-shape distal cover, whereas the latter species have boomerang shape distal covers. Olladiscoaster bordii is distinguished from Olladiscoaster perplexus and Olladiscoaster zucciae by having a petaloid proximal knob, whilst the latter species have hexagon proximal knobs. Olladiscoaster exagonikoasteri and Olladiscoaster catinatus lack a proximal knob.

References

Varol, O. & Bowman, A. R. 2024. The New Middle Miocene Genus Olladiscoaster, and Related and Associated Discoasters. Grzybowski Foundation Special Publication, 28: 1-103 pp.

Taxonomy

Olladiscoaster

Biostratigraphy

Stratigraphic Range

Serravalian

Zone(s)

NN5 - NN6

Age (Ma)

13.72 - 13.00

Holotype

Olladiscoaster bordii Varol & Bowman, 2024

Middle Miocene

USGS-NASA Langley Core, Hampton, VA (USA)