Helicosphaera epimikeisporous

Varol, 2025 Jan 17, 2022

Set number: 1446

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10µm

Helicosphaera epimikeisporous, Early Pliocene, DSDP Leg 23, Site 225, Red Sea

Set number: 1447

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10µm

Helicosphaera epimikeisporous, Late Miocene, DSDP Leg 23, Site 225, Red Sea

Set number: 1449

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10µm

Helicosphaera epimikeisporous, Early Pliocene, DSDP Leg 23, Site 225, Red Sea

Set number: 1450

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10µm

Helicosphaera epimikeisporous, Middle Miocene, Antakya, Hatay, Turkey

Set number: 1267

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10µm

Helicosphaera epimikeisporous, Middle Pleistocene, DSDP Leg 23 Site 229A, Red Sea

Set number: 1266

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10µm

Helicosphaera epimikeisporous, Middle Pleistocene, DSDP Leg 23 Site 229A, Red Sea

Set number: 1265

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10µm

Helicosphaera epimikeisporous, Middle Pleistocene, DSDP Leg 23 Site 229A, Red Sea

Set number: 1264

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10µm

Helicosphaera epimikeisporous, Late Pleistocene, DSDP Leg 23 Site 229A, Red Sea

Set number: 1263

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10µm

Helicosphaera epimikeisporous, Late Pleistocene, DSDP Leg 23 Site 229A, Red Sea

Set number: 314

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10µm

Helicosphaera epimikeisporous, Late Pleistocene, Menai Straight_SOS Core

Set number: 1268

Helicosphaera epimikeisporous

Fig. 1 Middle Miocene, Antakya, Hatay, Turkey, 8.2µm;

Fig. 2 Middle Miocene, Malta, 6.5µm;

Fig.3 Middle Miocene, Antakya, Hatay, Turkey, 7.3µm

Fig.4 Extant, Jason Bay, The South China Sea, 10.84µm

Final Epithet

Helicosphaera epimikeisporous Varol, 2025

Basionym

Helicosphaera epimikeisporous Varol, 2025

Diagnosis

A helicolith characterised by a Type III (Helicosphaera carteri type) blanket, an expanded flange termination, and a proximal plate with two large elongated pores arranged along the long axis of the coccolith.

Etymology

The species name epimikeisporous is derived from the Greek epimikeis, meaning “elongated,” and porous, meaning “pores,” referring to the two elongated pores in the central area.

Description

Optical Properties: Helicosphaera epimikeisporous exhibits inclined extinction angles of about 52° on the blanket on the distal side and shows length-fast (−) elongation.

Remarks

Helicosphaera epimikeisporous is distinguished from Helicosphaera carteri and Helicosphaera kamptneri by the elongated shape of its pores in the proximal plate. In contrast, Helicosphaera carteri possesses semi-circular pores, while Helicosphaera kamptneri has tiny, barely visible pores.

References

Varol, O. 2025. A practical guide to optical studies of calcareous nannofossils. Grzybowski Foundation Special Publication, 29, 222 pp.