• Diphasia Agassiz, 1862 [Class: Hydrozoa]
• Diphasia Fischer, 1823 (uncertain) [Class: Protozoa (awaiting allocation)]
• Diphasia Pierre, 1898 accepted as Vepris Commerson ex A.H.L. Jussieu, 1825 [Class: Magnoliopsida]
• Diphasia alata (Hincks, 1855)
• Diphasia alternitheca Kudelin, 1914 accepted as Abietinaria alternitheca (Kudelin, 1914)
• Diphasia attenuata (Hincks, 1866)
• Diphasia bipinnata Allman, 1885
• Diphasia cauloatheca Billard, 1920
• Diphasia corniculata (Murray, 1860)
• Diphasia cristata Billard, 1920
• Diphasia delagei (Billard, 1912)
• Diphasia densa (Stechow, 1923)
• Diphasia derbeki Kudelin, 1913 accepted as Abietinaria derbeki (Kudelin, 1913)
• Diphasia digitalis (Busk, 1852)
• Diphasia dubia Hargitt, 1927
• Diphasia elegans G.O. Sars, 1874 accepted as Diphasia margareta (Hassall, 1841)
• Diphasia fallax (Johnston, 1847)
• Diphasia heurteli Billard, 1924
• Diphasia inornata Nutting, 1927
• Diphasia kincaidi Nutting, 1901
• Diphasia margareta (Hassall, 1841)
• Diphasia minuta Billard, 1920
• Diphasia mutulata (Busk, 1852)
• Diphasia nigra (Pallas, 1766)
• Diphasia nuttingi Stechow, 1913
• Diphasia orientalis Billard, 1920
• Diphasia paarmani Nutting, 1904
• Diphasia palmata Nutting, 1905
• Diphasia pinaster sensu Hincks, 1868
• Diphasia pinastrum (Cuvier, 1830)
• Diphasia pulchra Nutting, 1904
• Diphasia rectangularis Lendenfeld, 1884
• Diphasia robusta Fraser, 1943
• Diphasia rosacea (Linnaeus, 1758)
• Diphasia scalariformis Kirkpatrick, 1890
• Diphasia spasskii Fenyuk, 1947 accepted as Papilionella spasskii (Fenyuk, 1947)
• Diphasia subcarinata (Busk, 1852)
• Diphasia tetraglochina Billard, 1907
• Diphasia thornelyi Ritchie, 1909
• Diphasia tropica Nutting, 1904
• Diphasia varians Jarvis, 1922
• Diphasia wandeli Levinsen, 1893
• Diphasiastrum Holub, 1975 accepted as Lycopodium Linnaeus, 1753
• Diphasiastrum alpinum (L.) Holub accepted as Lycopodium alpinum Linnaeus
• Diphasiastrum complanatum (L.) Holub accepted as Lycopodium complanatum Linnaeus
• Diphasiastrum digitatum (Dill. ex A. Braun) Holub accepted as Lycopodium digitatum Dill. ex A. Braun
• Diphasiastrum habereri (House) Holub accepted as Lycopodium habereri House
• Diphasiastrum issleri (Rouy) Holub accepted as Lycopodium issleri (Rouy) Domin
• Diphasiastrum sabinifolium (Willd.) Holub accepted as Lycopodium sabinifolium Willd.
• Diphasiastrum sitchense (Rupr.) Holub accepted as Lycopodium sitchense Rupr.
• Diphasiastrum tristachyum (Pursh) Holub accepted as Lycopodium tristachyum Pursh
• Diphasiastrum zeilleri (Rouy) Holub accepted as Lycopodium zeilleri (Rouy) Greuter & Burdet