Discoaster hughesii
Set number: 3864
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10µm
Holotype in the mobile mount
Discoaster hughesii Varol & Bowman, 2024
1984 Discoaster musicus Stradner, 1959 – Theoderidis, pp. 164-165, non Pl. 34, Figs. 15-18; Pl. 35, Fig.5
Species have six gently tapering arms that terminate in bifurcation. The length of the arms is about equal to the diameter of the central area. The inter-arm area is rounded, as shown in Discoaster deflandrei and Discoaster emblematicus. The distal side of the relatively large central area is ornamented with prominent sutural ridges created by deep cavities and blanketed by distal covers. In contrast, the proximal ridges adorn the bulged proximal side of the central area.
In honour of Dr G. W. Hughes, micropaleontologist, Ruthin, North Wales, UK.
Maximum diameter: 11.09 µm, Diameter of the central area: 4.11 µm, Length of the arms: 3.49 µm, maximum height: 4.41 µm (measurements from bright field micrograph).
Discoaster hughesii differs from Discoaster musicus and Discoaster sanmiguelensis by having longer tapering arms with distinct bifurcations. Discoaster hughesii is further distinguished from Discoaster sanmiguelensis by having proximal ridges, whereas the latter species has a proximal platform. Discoaster hughesii is differentiated from Discoaster deflandrei and Discoaster emblematicus by having a proximally bulged central area with distinct ridges. No ornamentation is on the proximal side of the Discoaster deflandrei and Discoaster emblematicus. The sutural ridges are absent in Discoaster deflandrei but indistinct in Discoaster emblematicus. Discoaster hughesii is identified from Discoaster gizoensis and Discoaster ulnatus by having a proximally bulged central area, prominent sutural ridges, rounded inter-arm areas, and well-developed bifurcations.
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.
Holotype
Discoaster hughesii
Varol & Bowman, 2024
Late Miocene
IODP Expedition 354, Hole U1451B, Bengal Fan, Indian Ocean