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Keywords from Image Description:
Radiolaria Challenger Plate . follows Plate Dorataspida et Belonaspida Diam Fig Tessaraspis arachnoides sp Fig Icosaspis tabulata sp Fig Icosaspis icosastaura sp Fig Icosaspis elegans sp Fig Tessaraspis concreta sp Fig Phatnaspis cristata sp Fig Phatnaspis haliommidium sp Central capsule within the shell outline