Olladiscoaster perplexus Varol & Bowman, 2024
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 almost aligned to the vertices of the species and are distinctly raised towards the centre and capped by kite-shaped distal covers. The distinct proximal ridges with a hexagonal-stellate knob decorate the bulged proximal side. At the side view, Olladiscoaster per-plexus resembles a bouquet.
From the Latin perplexus, confused – refers to the very unusual close alignment of the sutural ridges to the apices of the species.
Maximum diameter: 6.43 µm, Maxi-mum height: 5.8 µm; Diameter of the proximal knob: 3.53 µm, Height of the proximal knob: 1.25 µm (measurements from bright field micrograph)
Olladiscoaster perplexus and Olladiscoaster exagonikoasteri have hexagonal outlines, and their sutural ridges are almost aligned with the vertices of the species. Olladiscoaster perplexus differs from Olladiscoaster exagonikoasteri by having kite shape distal cover and a hexagon-stellate proximal knob, whereas the latter has a boomerang shape distal cover and lacks a proximal knob.
Varol, O. & Bowman, A. R. 2024. The New Middle Miocene Genus Olladiscoaster, and Related and Associated Discoasters. Grzybowski Foundation Special Publication, 28, 103 pp.