• Myriactis Haddon, 1888 [Family: Stichodactylidae]
• Myriactis Kützing, 1843 accepted as Myriactula O. Kuntze, 1898 [Family: Chordariaceae]
• Myriactis Lessing, 1831 [Family: Asteraceae]
• Myriactis adriatica (J.G. Agardh) De Toni, 1885 accepted as Corynophlaea flaccida (C. Agardh) Kützing, 1858
• Myriactis arabica (Kützing) Kuckuck, 1929 accepted as Myriactula arabica (Kützing) Feldmann, 1937
• Myriactis areschougii (P.L. Crouan & H.M. Crouan) Batters, 1892 accepted as Myriactula areschougii (P.L. Crouan & H.M. Crouan) G. Hamel, 1935
• Myriactis cystophorae (J.G. Agardh) Kuckuck, 1929 accepted as Corynophlaea cystophorae J.G. Agardh, 1882
• Myriactis elongata Sauvageau, 1936 accepted as Myriactula elongata (Sauvageau) G. Hamel, 1939
• Myriactis haydenii (Gatty) Batters, 1902 accepted as Myriactula haydenii (Gatty) Levring, 1937
• Myriactis microscopica Ercegovic, 1948 accepted as Myriactula microscopica (Ercegovic) Ercegovic, 1957
• Myriactis moniliformis (Foslie) Kylin, 1910 accepted as Myriactula haydenii (Gatty) Levring, 1937
• Myriactis oxalifera Sauvageau, 1936 accepted as Myriactula oxalifera (Sauvageau) G. Hamel, 1939
• Myriactis pulvinata Kützing, 1843 accepted as Myriactula pulvinata (Kützing) Kuntze, 1898
• Myriactis rigida Sauvageau, 1936 accepted as Myriactula rigida (Sauvageau) G. Hamel, 1939
• Myriactis sargassi Yendo, 1920 accepted as Myriactula sargassi (Yendo) Feldmann, 1945
• Myriactis stellulata (Harvey) Batters, 1892 accepted as Myriactula stellulata (Harvey) Levring, 1937
• Myriactis tubicola Haddon, 1888