Kingdom Plantae Haeckel (1866) - plants Subkingdom Rhodoplantae G.W.Saunders & Hommers. (2004) Phylum Rhodophyta Wettst. (1901) - red algae Subphylum Rhodellophytina Caval.-Sm. (1998) [monotypic] Class Rhodellophyceae Caval.-Sm. (1998) [paraphyletic?] Order Porphyridiales Kylin ex Skuja (1939) Genus Porphyridium Nägeli (1849), nom. cons.