acanthophractida acanthophractida acanthophractida is an order of marine radiolarians in the subclass acantharia; skeleton includes a latticework shell and skeletal rods. they have a latticework shell, which can be spherical or ovoid and fused with the skeletal rods. the shell is concentric with the central capsule. "the body is usually covered with a single or double gelatinous sheath through which the skeletal rods emerge". acanthophractida scientific classification domain: eukaryota (unranked): sar (unranked): rhizaria phylum: retaria subphylum: radiolaria class: acantharea order: acanthophractida