Discoaster stellimicros

Pospichal & Bergen in de Kaenel et al., 2017 Jan 31, 2025

Set number: 3877

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10µm

Discoaster stellimicros, Middle Miocene, IODP Expedition 354, Hole U1451B, Bengal Fan, Indian Ocean

In the mobile mount.

Set number: 3878

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10µm

Discoaster stellimicros, Middle Miocene, ODP Leg 154, Hole 926A, Ceará Rise, western equatorial Atlantic.

In the mobile mount.

Set number: 3879

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10µm

Discoaster stellimicros, Middle Miocene, ODP Leg 154, Hole 926A, Ceará Rise, western equatorial Atlantic.

In the mobile mount.

Final Epithet

Discoaster stellimicros Pospichal & Bergen in de Kaenel et al., 2017

Basionym

Discoaster stellimicros Pospichal & Bergen in de Kaenel et al., 2017

Synonyms

2017 Discoaster stellimicros Pospichal & Bergen in De Kaenel et al., (pro parte), pp. 229-230, non Pl. 5 Fig.21 (paratype); Pl.5 Fig. 22-23 (holotype).

Description

Emended description: Relatively small six-segmented species have a large central area decorated with prominent sutural ridges created by deep cavities on the distal side. On the proximal side, ridges construct a platform-like structure on the bulging central area. Careful focus is required to identify the proximal platform. The arms are bifurcated, and their lengths are much shorter than the diameter Diameter of the central area (less than half). The inner-arm areas are much wider than deeper.

Remarks

Discoaster stellimicros differs from Discoaster sanmiguelensis in that it is small and has very short arms. Discoaster stellimicros is distinguished from Discoaster pugliesei by having much wider and deeper inter-arm areas (half moon shape), whereas the latter has round, almost eclosed inter-arm areas. The inter-arm area is shallow but much wider in Discoaster catillomicros. The presence of distinct sutural ridges and deep cavities differentiate Discoaster stellimicros from Discoaster micros.

References

De Kaenel, E., Bergen, J. A., Browning, E., Blair, S. A. & Boesiger, T.M. 2017. Uppermost Oligocene to Middle Miocene Discoaster and Catinaster taxonomy and stratigraphy in the circum North Atlantic Basin, Gulf of Mexico and ODP Leg 154. Journal of Nannoplankton Research, 37 (2-3): 215–244.

Taxonomy

Discoaster

Biostratigraphy

Stratigraphic Range

Serravalian - Tortonian

Zone(s)

NN6 - NN8

Age (Ma)

13.40 - 11.58

Holotype

Discoaster stellimicros Pospichal & Bergen in de Kaenel et al., 2017

Middle Miocene

ODP Leg 154, Hole 926A, Ceará Rise, western equatorial Atlantic.