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Keywords from Image Description:
Radiolaria Challenger Plate . follows Plate Sphrocapsida Dorataspida et Phractopeltida Diam Fig Phractopelta dorataspis sp Fig Dorypelta tessaraspis sp Fig Stauropelta cruciata sp Fig Pantopelta icosaspis sp Meridional section through the double shell Fig Octopelta scutella sp Proximal part of two meeting spines isolated