Discoaster virginianus

Discoaster virginianus (Self-Trail, 2014) de Kaenel & Bergen in de Kaenel et al., 2017

1993 Catinaster sp. Aubry (pro parte), Pl. 2, Figs. 12, 16; Pl. 3, figs. 11–15; non Pl. 3, Figs. 17-19

2017 Discoaster gamberi de Kaenel & Bergen in de Kaenel et al., p. 228, Pl. .5, Figs 5-10 (preservational morphotype).

Emended description: This species has six segments with slender arms terminating in notches, a large central area with sutural ridges created by deep cavities on the distal side, and a hexagonal knob created by ridges on the bulged proximal side. The arms of the segments are about equal to half of the central area in complete specimens. The sutural ridges are raised towards the centre and capped by boomerang-shaped distal covers.

Discoaster virginianus differs from Discoaster self-trailiae and Discoaster artatus by having a hexagonal proximal knob. Discoaster self-trailiae has a petaloid proximal knob, whereas Discoaster artatus lacks a proximal knob. The delicate arms of Discoaster virginianus, Discoaster self-trailiae and Discoaster artatus are prone to be broken. Discoaster gamberi, therefore, is considered a preservational morphotype of Discoaster virginianus

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.

Self-Trail, J. 2014. Catinaster virginianus sp. nov., A new species of Catinaster from the middle Miocene Mid-Atlantic Coastal Plain. Journal of Nannoplankton Research, 33 (1): 49–57.

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.