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Keywords from Image Description:
Radiolaria Challenger Plate . follows Plate Phacodiscida Diam Fig Sethostylus dentatus sp vel Heliostylus dentatus Upper half of the disk Fig Sethostylus serratus sp vel Heliostylus serratus Lower half of the disk Fig Heliosestrum octonum sp Fig Heliodiscus solaster sp Fig Heliodiscus echiniscus sp Fig Heliosestrum