retaria retaria retaria is a clade within the supergroup rhizaria containing the foraminifera and the radiolaria. in 2019, the retaria were recognized as a basal rhizaria group, as sister of the cercozoa. retaria live ammonia tepida scientific classification domain: eukaryota clade: diaphoretickes clade: tsar clade: sar clade: rhizaria phylum: retariacavalier-smith, 1999 subphyla foraminifera radiolaria sar supergroup rhizaria cercozoa retaria foraminifera polycystinea acantharea sticholonchea halvaria stramenopiles alveolata