Kingdom Plantae Haeckel (1866) - plants Subkingdom Rhodoplantae G.W.Saunders & Hommers. (2004) Phylum Rhodophyta Wettst. (1901) - red algae Subphylum Eurhodophytina G.W.Saunders & Hommers. (2004) Class Florideophyceae Cronquist (1960) Subclass Ahnfeltiophycidae G.W.Saunders & Hommers. (2004) 1 Order Ahnfeltiales Maggs & Pueschel (1989) 2 Order Pihiellales Huisman, A.R.Sherwood & I.A.Abbott (2003)