• Leptonema A.H.L. Jussieu, 1824 [Family: Phyllanthaceae, Phylum: Tracheophyta]
• Leptonema Guérin-Meneville, 1844 [Family: Hydropsychidae, Phylum: Arthropoda]
• Leptonema Hovind-Hougen, 1983 [Family: Leptospiraceae, Phylum: Spirochaetae]
• Leptonema Ijima, 1927 (uncertain) [Family: Porifera (awaiting allocation), Phylum: Porifera]
• Leptonema J. Smith Dalry, 1896 † [Family: , Phylum: Fungi (awaiting allocation)]
• Leptonema Jairajpuri, 1964 accepted as Dorylaimoides Thorne & Swanger, 1936 [Family: Mydonomidae, Phylum: Nematoda]
• Leptonema L. Rabenhorst, 1857 (unaccepted) [Family: Cyanophyceae (awaiting allocation), Phylum: Cyanobacteria]
• Leptonema Lendenfeld, 1915 accepted as Cyliconemaoida Dohrmann, 2017 accepted as Hyalonema Gray, 1832 [Family: Hyalonematidae, Phylum: Porifera]
• Leptonema Reinke, 1888 accepted as Leptonematella P.C. Silva, 1959 [Family: Chordariaceae, Phylum: Ochrophyta]
• Leptonema W.J. Hooker, 1844 accepted as Draba Linnaeus, 1753 [Family: Brassicaceae, Phylum: Tracheophyta]
• Leptonema aberrans Flint, McAlpine & Ross, 1987
• Leptonema aconicum Chvojka & Sykora, 1999
• Leptonema acuferum (Schulze, 1893) accepted as Hyalonema acuferum Schulze, 1893
• Leptonema acutum Mosely, 1933
• Leptonema affine Ulmer, 1905
• Leptonema agraphum (Kolenati, 1859)
• Leptonema alatum Marlier, 1961
• Leptonema albovirens (Walker, 1852)
• Leptonema album Mosely, 1933
• Leptonema alceatum Flint, McAlpine & Ross, 1987
• Leptonema amazonense Flint, 1978
• Leptonema andinum Flint, 1991
• Leptonema andrea Flint, McAlpine & Ross, 1987
• Leptonema araguense Flint, 1981
• Leptonema archboldi Flint, 1968
• Leptonema arcticum A.D. Zinova, 1957
• Leptonema asclepium Flint, McAlpine & Ross, 1987
• Leptonema aspersum (Ulmer, 1907)
• Leptonema aterrimum Mosely, 1933
• Leptonema auriculatum Flint, McAlpine & Ross, 1987
• Leptonema banksi Mosely, 1933
• Leptonema bifurcatum Flint, McAlpine & Ross, 1987
• Leptonema bilobatum Schmid, 1964
• Leptonema boliviense Mosely, 1933
• Leptonema boraceia Flint, McAlpine & Ross, 1987
• Leptonema campanum Flint, McAlpine & Ross, 1987
• Leptonema championi Mosely, 1933
• Leptonema cheesmanae Mosely, 1933
• Leptonema chiapense Flint, McAlpine & Ross, 1987
• Leptonema chila Flint, 1967
• Leptonema choaniferum Lévi, 1964 accepted as Hyalonema choaniferum (Lévi, 1964)
• Leptonema chocoense Flint, McAlpine & Ross, 1987
• Leptonema cinctum Ulmer, 1905
• Leptonema clorito Munioz-Quesada, 1997
• Leptonema coheni Flint, McAlpine & Ross, 1987
• Leptonema columbianum Ulmer, 1905
• Leptonema complexum Mosely, 1933
• Leptonema conicum Flint, McAlpine & Ross, 1987
• Leptonema crassum Ulmer, 1905
• Leptonema davisi Flint, McAlpine & Ross, 1987
• Leptonema displicens (Navas, 1935)
• Leptonema divaricatum Flint, McAlpine & Ross, 1987
• Leptonema dyeri Flint, McAlpine & Ross, 1987
• Leptonema ekisi Flint, McAlpine & Ross, 1987
• Leptonema eugnathum (Mueller, 1921)
• Leptonema falklandicum Skottsberg, 1907 accepted as Leptonematella falklandica (Skottsberg) M.J. Wynne, 1969
• Leptonema fasciculatum Reinke, 1888 accepted as Leptonematella fasciculata (Reinke) P.C. Silva, 1959
• Leptonema flintorum Munioz-Quesada, 1997
• Leptonema forficulum Mosely, 1933
• Leptonema fortunum Flint, McAlpine & Ross, 1987
• Leptonema furciligerum Flint, McAlpine & Ross, 1987
• Leptonema gadzux Flint, McAlpine & Ross, 1987
• Leptonema glabrum (Leandri) Leandri
• Leptonema guayanense Flint, McAlpine & Ross, 1987
• Leptonema guineense Gibbs, 1973
• Leptonema hamuli Flint, McAlpine & Ross, 1987
• Leptonema harpagum Flint, McAlpine & Ross, 1987
• Leptonema heppneri Flint, McAlpine & Ross, 1987
• Leptonema hirsutum Flint, 1974
• Leptonema huismanae Munioz-Quesada, 1997
• Leptonema illini Hovind-Hougen, 1983
• Leptonema inca Mosely, 1933
• Leptonema inspiratum Flint, McAlpine & Ross, 1987
• Leptonema insulanum Banks, 1924
• Leptonema intermedium Mosely, 1933
• Leptonema irroratum Flint, 1974
• Leptonema lacuniferum Flint, 1978
• Leptonema latipenne Marlier, 1947
• Leptonema lojaense Flint, McAlpine & Ross, 1987
• Leptonema lucifugum Kuckuck, 1897 accepted as Pilinia rimosa Kützing, 1843
• Leptonema lunatum Flint, McAlpine & Ross, 1987
• Leptonema machadoi Marlier, 1965
• Leptonema maculatum Mosely, 1933
• Leptonema madagascariense Ulmer, 1905
• Leptonema mandibulatum Flint, McAlpine & Ross, 1987
• Leptonema marlieri Flint, McAlpine & Ross, 1987
• Leptonema mastigion Flint, McAlpine & Ross, 1987
• Leptonema melanthesoides F. Muell. accepted as Flueggea virosa (Roxb. ex Willd.) Voigt
• Leptonema menkei Flint, McAlpine & Ross, 1987
• Leptonema michoacanense Flint, McAlpine & Ross, 1987
• Leptonema milae Sykora, 1964
• Leptonema moselyi Flint, McAlpine & Ross, 1987
• Leptonema natalense Mosely, 1933
• Leptonema neadelphus Flint, McAlpine & Ross, 1987
• Leptonema neapolitanum Schussnig, 1930 accepted as Leptonematella neapolitana (Schussnig) Cormaci & G. Furnari, 1992
• Leptonema neblinense Flint, McAlpine & Ross, 1987
• Leptonema niveum Rabenhorst
• Leptonema normale Banks, 1920
• Leptonema nupharum Flint, McAlpine & Ross, 1987
• Leptonema occidentale Ulmer, 1907