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Keywords from Image Description:
Radiolaria Challenger Plate . follows Plate Tripocalpida et Phnocalpida Diam Fig Euscenium plectaniscus sp Half frontal half basal view Fig Cladoscenium pectinatum sp Shell opened by vertical section Fig Archiscenium cyclopterum sp View from the dorsal side Fig Pteroscenium arcuatum sp The central capsule contains