Olladiscoaster zucciae Varol & Bowman, 2024
Circular to 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 raised towards the centre and capped by kite-shaped distal covers. The distinct proximal ridges with a hexagon-stellate knob at the centre decorate the bulged proximal side. At the side view, Olladiscoaster zucciae resembles a bouquet.
In honour of the late Donata Zucci, a nannofossil specialist from Italy.
Maximum diameter: 6.46 µm, Maximum height: 5.43 µm; Diameter of the proximal knob: 4.04 µm, Height of the proximal knob: 1.33 µm (measurements from bright field micrograph).
Olladiscoaster zucciae differs from Olladiscoaster cruzii, Olladiscoaster catinatus and Olladiscoaster asterilithos by having a kite shape distal cover, whereas the latter species have boomerang shape distal covers. Olladiscoaster zucciae is distinguished from Olladiscoaster bordii by having a hexagon-stellate proximal knob, whilst the latter species have pet-aloid proximal knobs. Olladiscoaster zucciae is differentiated from Olladiscoaster exagonikoasteri and Olladiscoaster perplexus by having sutural ridges bisecting the periphery at the middle, whilst later species have sutural ridges almost aligned with the vertices. Moreover, Olladiscoaster exagonikoasteri 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.