GURGEL, Carlos Frederico D., James N. NORRIS, William E. SCHMIDT, Hau Nhu LE & Suzanne FREDERICQ 2018 (Nov. 1) Systematics of the Gracilariales (Rhodophyta) including new subfamilies, tribes, subgenera, and two new genera, Agarophyton gen. nov. and Crassa gen. nov. Phytotaxa 374(1): 1-23, 3 figs., 1 table