Actinoptychus simbirskianus Schmidt (1875)
Comment: Large, well-preserved valve. Note the zones of sparse perforations along the distal edges of the depressed sectors.
Locality: Smolkovo, Ulyanovsk District, Russia, sample: Hustedt collection sample E1708 (late Paleocene).
Photographed using: Zeiss Axio.A1, EC Plan-NEOFLUAR 40×/0.75 + Zeiss AxioCam ICc 5. Stacked using Helicon Focus.
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