• Abrochtha carnivora Ricci, Melone & Walsh, 2001
• Abrochtha intermedia (Beauchamp, 1909)
• Abrochtha kingi Birky, Ricci, Melone & Fontaneto, 2011
• Abrochtha meselsoni Birky, Ricci, Melone & Fontaneto, 2011
• Abrochtha sonneborni Birky, Ricci, Melone & Fontaneto, 2011
• Acanthodactylus gracilis Tessin, 1890 accepted as Trichocerca gracilis (Tessin, 1890)
• Actinurus neptunius Ehrenberg, 1830 accepted as Rotaria neptunia (Ehrenberg, 1830)
• Actinurus ovatus Anderson, 1889 accepted as Rotaria ovata (Anderson, 1889)
• Acyclus inquietus Leidy, 1882
• Adactyla verrucosa Barrois & Daday, 1894 (uncertain > taxon inquirendum)
• Adineta acuticornis Haigh, 1967
• Adineta alluaudi Certes, 1903 accepted as Adineta oculata (Milne, 1886)
• Adineta barbata Janson, 1893
• Adineta bartosi Wulfert, 1960
• Adineta beysunae Örstan, 2018
• Adineta clauda Bryce, 1893 accepted as Bradyscela clauda (Bryce, 1893)
• Adineta coatsi Iakovenko, Smykla, Convey, Kasparona, Kozeretska, Trokhymets, Dykyy, Plewka, Devetter & Janko, 2015
• Adineta cuneata Milne, 1916
• Adineta donneri Bielanska-Grajner, Ejsmont-Karabin & Iakovenko, 2013 (unaccepted)
• Adineta editae Iakovenko, 2015
• Adineta elongata Rodewald, 1935
• Adineta emsliei Iakovenko, Smykla, Convey, Kasparona, Kozeretska, Trokhymets, Dykyy, Plewka, Devetter & Janko, 2015
• Adineta fontanetoi Iakovenko, Smykla, Convey, Kasparona, Kozeretska, Trokhymets, Dykyy, Plewka, Devetter & Janko, 2015
• Adineta glauca Wulfert, 1942
• Adineta gracilis Janson, 1893
• Adineta grandis Murray, 1910
• Adineta longicornis Murray, 1906
• Adineta oculata (Milne, 1886)
• Adineta rhomboidea Bērziņš, 1950
• Adineta ricciae Segers & Shiel, 2005
• Adineta steineri Bartoš, 1951
• Adineta tuberculosa Janson, 1893
• Adineta vaga (Davis, 1873)
• Adineta vaga major Bryce, 1893
• Adineta vaga minor Bryce, 1893
• Adineta vaga rhomboidea Bērziņš, 1950 accepted as Adineta rhomboidea Bērziņš, 1950
• Adineta vaga tenuicornis Bryce, 1926
• Adineta vaga var. major Bryce, 1893 accepted as Adineta vaga major Bryce, 1893
• Adineta vaga var. minor Bryce, 1893 accepted as Adineta vaga minor Bryce, 1893
• Adineta vaga var. tenuicornis Bryce, 1926 accepted as Adineta vaga tenuicornis Bryce, 1926
• Albertia aciliata Radkewitsch, 1870 accepted as Balatro aciliatus (Radkewitsch, 1870)
• Albertia bernardi Hlava, 1905 accepted as Albertia naidis Bousfield, 1886
• Albertia caudata Manfredi, 1927 accepted as Albertia naidis Bousfield, 1886
• Albertia crystallina Schultze, 1851
• Albertia intrusor Gosse, 1886 accepted as Albertia naidis Bousfield, 1886
• Albertia naidis Bousfield, 1886
• Albertia ovagranulata Valovaya, 1990
• Albertia reicheltae Koste, 1970
• Albertia soyeri Coineau & Kunst, 1964 accepted as Albertia naidis Bousfield, 1886
• Albertia typhlina Harring & Myers, 1928
• Albertia vermiculus Dujardin, 1838
• Albertia woronkowi Zenkewitsch, 1922
• Allodicranophorus bulgaricus (Althaus, 1957)
• Amphibolidina megalotrocha Schmarda, 1850 (uncertain > taxon inquirendum)
• Anapus ovalis Bergendal, 1892 accepted as Ascomorpha ovalis (Bergendal, 1892)
• Anchitestudinella mekongensis Bērziņš, 1973
• Anelcodiscus pellucidus Leidy, 1852 (uncertain > taxon inquirendum)
• Anomopus chasmagnathi Mane-Garzon & Montero, 1973
• Anomopus telphusae Piovanelli, 1903
• Anourella cithara Bory de St. Vincent, 1826 accepted as Brachionus pala Müller, 1786
• Anourella luth Bory de St. Vincent, 1826 accepted as Notholca squamula (Müller, 1786)
• Anourella lyra Bory de St. Vincent, 1826 accepted as Notholca striata (Müller, 1786)
• Anourella pandurina Bory de St. Vincent, 1826 accepted as Notholca bipalium (Müller, 1786)
• Anthos quadrilobus Schoch, 1868 (uncertain > taxon inquirendum)
• Anuraea aculeata Ehrenberg, 1832 accepted as Keratella quadrata (Müller, 1786)
• Anuraea aculeata f. curvata Bening, 1942 accepted as Keratella quadrata jakutica (Rylov, 1935)
• Anuraea aculeata resupina Imhof, 1892 (unaccepted > nomen nudum)
• Anuraea aculeata var. cochlearis Voigt, 1902 accepted as Keratella paludosa (Lucks, 1912)
• Anuraea aculeata var. conica Athanassopoulos, 1930 (uncertain > taxon inquirendum)
• Anuraea aculeata var. curvicornis (uncertain > taxon inquirendum)
• Anuraea aculeata var. curvicornis f. irregularis Jakubski, 1914 accepted as Keratella testudo irregularis Kutikova, 1970 accepted as Keratella irregularis (Lauterborn, 1898)
• Anuraea aculeata var. curvispina Steinecke, 1924 (uncertain > taxon inquirendum)
• Anuraea aculeata var. divergens Voigt, 1902 accepted as Keratella quadrata (Müller, 1786)
• Anuraea aculeata var. dumasi Richard, 1894 (uncertain > taxon inquirendum)
• Anuraea aculeata var. graeca Athanassopoulos, 1930 (uncertain > taxon inquirendum)
• Anuraea aculeata var. jakutica Rylov, 1935 accepted as Keratella quadrata jakutica (Rylov, 1935)
• Anuraea aculeata var. longispina Thiébaud, 1912 accepted as Keratella quadrata var. longispina (Thiébaud, 1912) accepted as Keratella quadrata (Müller, 1786)
• Anuraea aculeata var. platei Jägerskiöld, 1894 accepted as Keratella quadrata var. platei (Jägerskiöld, 1894) accepted as Keratella quadrata (Müller, 1786)
• Anuraea aculeata var. regalis Imhof, 1885 (unaccepted > nomen nudum)
• Anuraea aculeata var. ticinensis Callerio, 1920 accepted as Keratella ticinensis (Callerio, 1920)
• Anuraea aculeata vulgata Morozov, 1915 accepted as Keratella quadrata (Müller, 1786)
• Anuraea acuminata Ehrenberg, 1832 accepted as Notholca acuminata (Ehrenberg, 1832)
• Anuraea angulata Daday, 1906 accepted as Notholca angulata (Daday, 1906)
• Anuraea balthica Eichwald, 1852 (uncertain > taxon inquirendum)
• Anuraea biremis (uncertain)
• Anuraea biremis var. acuminata Loppens, 1907 (uncertain > taxon inquirendum)
• Anuraea brevispina Gosse, 1851 accepted as Keratella brevispina (Gosse, 1851) accepted as Keratella testudo (Ehrenberg, 1832)
• Anuraea clypeus Daday, 1906 accepted as Notholca clypeus (Daday, 1906)
• Anuraea cochlearis Gosse, 1851 accepted as Keratella cochlearis (Gosse, 1851)
• Anuraea cochlearis f. angulifera Lauterborn, 1900 accepted as Keratella irregularis f. angulifera (Lauterborn, 1900) accepted as Keratella irregularis (Lauterborn, 1898)
• Anuraea cochlearis f. connectens Lauterborn, 1900 accepted as Keratella irregularis f. connectens (Lauterborn, 1900) accepted as Keratella irregularis (Lauterborn, 1898)
• Anuraea cochlearis f. micracantha Lauterborn, 1900 accepted as Keratella cochlearis f. micracantha (Lauterborn, 1900) accepted as Keratella cochlearis (Gosse, 1851)
• Anuraea cochlearis f. tuberculata Lauterborn, 1900 accepted as Keratella cochlearis f. tuberculata (Lauterborn, 1900) accepted as Keratella cochlearis (Gosse, 1851)
• Anuraea cochlearis pellucida Imhof, 1892 (unaccepted > nomen nudum)
• Anuraea cochlearis var. baltica Imhof, 1886 accepted as Keratella cochlearis var. baltica Imhof, 1886
• Anuraea cochlearis var. baltica Sokolova, 1927 accepted as Keratella cochlearis var. baltica Sokolova, 1927 accepted as Keratella cochlearis f. macracantha (Lauterborn, 1898) accepted as Keratella cochlearis (Gosse, 1851)
• Anuraea cochlearis var. carinata Levander, 1891 accepted as Keratella cochlearis var. carinata (Levander, 1891)
• Anuraea cochlearis var. hispida Lauterborn, 1898 accepted as Keratella cochlearis var. hispida (Lauterborn, 1898) accepted as Keratella cochlearis (Gosse, 1851)
• Anuraea cochlearis var. hispida f. ecauda Ammann, 1921 accepted as Keratella cochlearis var. hispida f. ecauda (Ammann, 1921) accepted as Keratella cochlearis (Gosse, 1851)
• Anuraea cochlearis var. hispida f. pustulata Lauterborn, 1900 accepted as Keratella cochlearis var. hispida f. pustulata (Lauterborn, 1900) accepted as Keratella cochlearis (Gosse, 1851)