Species (15.149)
- Orthodon banerjeei Ghosh 1921
- Orthodon parvirostrum Schewiakoff 1893
- Orthodon hamatus Gruber 1884
- Orthodonella macrocephala Ozaki & Yagiu 1943
- Orthodonella hamata Gruber 1884
- Orthokreyella schiffmanni Foissner 1984
- Ostracodinium bohor -> LB0002: 49
- Orthotrochilia agamalievi Deroux 1976
- Orthotrochilia pilula Deroux 1976
- Ostracodinium brazili -> LB0002: 49
- Ostracodinium caudatum -> LB0002: 49
- Ostracodinium crassum -> LB0002: 49
- Ostracodinium crustaceum -> LB0002: 49
- Ostracodinium clipeolum -> LB0002: 49
- Ostracodinium dentatum -> LB0002: 49 1889
- Ostracodinium dilobum -> LB0002: 49
- Ostracodinium dogieli -> LB0002: 49
- Ostracodinium dyurum -> LB0002: 49
- Ostracodinium esalqum -> LB0002: 49
- Ostracodinium gauri -> LB0002: 49
- Ostracodinium gladiator -> LB0002: 49
- Ostracodinium iwawoi -> LB0002: 49
- Ostracodinium gracilis -> LB0002: 49
- Ostracodinium mammosum -> LB0002: 49
- Ostracodinium minorum -> LB0002: 49
- Ostracodinium monolobum -> LB0002: 49
- Ostracodinium quadrivesiculatum -> LB0002: 49
- Nyctotherus befaysi Tuzet & Manier 1958
- Nyctotherus boipevae Carini 1933
- Nyctotherus buissoni Pinto 1926
- Nyctotherus delta Earl 1972
- Nyctotherus dilleri Earl & Jiménez 1969
- Nyctotherus diplopodae Karandikar & Rodgi 1956
- Nyctotherus ebriensis Gistler 1967
- Nyctotherus faba Schaudinn 1899
- Nyctotherus duboisii Künstler 1884
- Nyctotherus gamma Earl 1972
- Nyctotherus gisleri Earl 1972
- Nyctotherus gongylorrhus Karandikar & Rodgi 1956
- Nyctotherus grassei Earl 1972
- Nyctotherus gyoeranus Claparède & Lachmann 1858
- Nyctotherus haranti Grasse 1926
- Nyctotherus hormeticae Carini 1937
- Nyctotherus hoyai Tuzet & Theorides 1956
- Nyctotherus indica Baskar Rao 1969
- Nyctotherus jaboti Carini 1938
- Nyctotherus inflatus Tuzet & Manier 1958
- Nyctotherus mackinnoni Schouten 1940
- Nyctotherus kyphodes Geiman & Wichtermann 1937
- Nyctotherus madagascari Tuzet & Manier 1954
- Nyctotherus macropharyngeus
- Nyctotherus osmodermae Zeliff 1933
- Nyctotherus pachbolii Tuzet, Manier & Vogeli-Zuber 1952
- Nyctotherus pintoi Carini 1933
- Nyctotherus tipulae Grasse 1928
- Nyctotherus uichancoi Kidder 1937
- Nyctotherus velox Leidy 1849
- Ochridanus ocellatus Georgevitch 1941
- Oxytricha siseris Vuxanovici 1963
- Oxytricha sphagni Kahl 1932
- Oxytricha stenocephala Borror 1963
- Oxytricha stylomuscorum Foissner, Blatterer, Berger & Kohmann 1991
- Oxytricha stratiformis Dumas 1930
- Oxytricha subcylindrica Dumas 1929
- Oxytricha tricirrata Buitkamp 1977
- Oxytricha tetracirrata Gellert 1942
- Oxytricha tricornis Milne 1886
- Oxytricha urostyla Claparède & Lachmann 1858
- Oxytricha tubicola Gruber 1879
- Pachyfolliculina gunneri Dons 1927
- Pachystomos olisthus Rudzinska 1952
- Pachytrocha cothurnoides Kent 1882
- Palmarium latum Kahl 1927
- Palmarium salinum Gaievskaia 1925
- Panophrys conspicua Perty 1852
- Panophrys encarpa Dumas 1929
- Panophrys paramecioides Perty 1852
- Panophrys griseola Perty 1852
- Panophrys fusca Quennerstedt 1869
- Panophrys sordida Perty 1852
- Panophrys zonalis Perty 1852
- Pantotrichum enchelys Ehrenberg 1831
- Paracineta metridiae Sherman & Schaner 1965
- Paracineta oviformis Dons 1918
- Paraclathrostoma marina Roque 1961
- Paracineta patula Claparède & Lachmann 1859
- Paraclevelandia brevis Kidder 1937
- Paracoelophrya intermedia Puytorac 1969
- Paraclevelandia simplex Kidder 1937
- Paracoelophrya almae Puytorac 1969
- Paracollinia branchiarum Stein ()
- Paracolpoda aspera
- Paracolpoda elliotti
- Paracolpoda maupasi Lynn 1978
- Paracolpoda steini Maupas 1883
- Paracondylostoma cavistoma Gelei 1954
- Paractedectoma minuta Small & Lynn 1985
- Paracondylostoma setigerum Foissner 1980
- Paracyclidium circumlabens Small & Lynn 1985
- Paramecium aureolum Perty 1852