Achromadoridae Gerlach & Riemann, 1973 (basis of record)
Achromadorinae Gerlach & Riemann, 1973 (basis of record)
Actinonema Cobb, 1920 (additional source)
Actinonema celtica Boucher, 1976 (additional source)
Actinonema pachydermatum Cobb, 1920 (additional source)
Adoncholaiminae Gerlach & Riemann, 1974 (additional source)
Aegialoalaimidae Lorenzen, 1981 (additional source)
Aegialoalaimus de Man, 1907 (additional source)
Aegialoalaimus elegans de Man, 1907 (additional source)
Amphimonhystera Allgén, 1929 (additional source)
Amphimonhystera anechma (Southern, 1914) Lorenzen, 1977 (additional source)
Anoplostoma Bütschli, 1874 (additional source)
Anoplostomatidae Gerlach & Riemann, 1974 (additional source)
Anoplostomatinae (additional source)
Anticoma Bastian, 1865 (additional source)
Anticoma acuminata (Eberth, 1863) Bastian, 1865 (additional source)
Anticoma eberthi Bastian, 1865 (additional source)
Anticoma pellucida Bastian, 1865 accepted as Anticoma limalis novozemelica Filipjev, 1927 accepted as Anticoma acuminata (Eberth, 1863) Bastian, 1865 (additional source)
Anticomidae Filipjev, 1918 (additional source)
Antomicron Cobb, 1920 (additional source)
Antomicron elegans (de Man, 1922) De Coninck, 1965 (additional source)
Aponema Jensen, 1978 (additional source)
Aponema torosus (Lorenzen, 1973) Jensen, 1978 accepted as Aponema torosum (Lorenzen, 1973) Jensen, 1978 (basis of record)
Araeolaimus de Man, 1888 (additional source)
Araeolaimus elegans de Man, 1888 (additional source)
Araeolaimus microphthalmus (de Man, 1893) Filipjev, 1918 accepted as Araeolaimoides microphthalmus de Man, 1893 (additional source)
Araeolaimus penelope Moore, 1977 (additional source)
Atrochromadora Wieser, 1959 (additional source)
Atrochromadora microlaima (de Man, 1889) Wieser, 1954 (additional source)
Atrochromadora parva (de Man, 1893) Wieser, 1954 (additional source)
Axonolaimidae Filipjev, 1918 (additional source)
Axonolaimoidea Filipjev, 1918 (additional source)
Axonolaimus de Man, 1889 (additional source)
Axonolaimus filiformis de Man, 1889 (additional source)
Axonolaimus helgolandicus Lorenzen, 1971 (additional source)
Axonolaimus hexapilus Wieser & Hopper, 1967 (additional source)
Axonolaimus orcombensis Warwick, 1970 (additional source)
Axonolaimus paraspinosus Schuurmans Stekhoven & Adam, 1931 (additional source)
Bathylaimus Cobb, 1894 (additional source)
Bathylaimus australis Cobb, 1894 (additional source)
Bathylaimus capacosus Hopper, 1962 (additional source)
Bathylaimus filicaudatus (Schuurmans Stekhoven & Adam, 1931) De Coninck & Schuurmans Stekhoven, 1933 (additional source)
Bathylaimus paralongisetosus Schuurmans Stekhoven & De Coninck, 1933 (additional source)
Bathylaimus stenolaimus Schuurmans-Stekhoven & De Coninck, 1933 (additional source)
Bathylaimus tenuicaudatus (Allgén, 1933) Allgen, 1947 (additional source)
Bolbolaimus Cobb, 1920 (additional source)
Bolbolaimus teutonicus (Riemann, 1966) Jensen, 1978 (additional source)
Calomicrolaimus Lorenzen, 1976 (additional source)
Calomicrolaimus acanthus (Jayasree & Warwick, 1977) Jensen, 1978 accepted as Microlaimus acanthus (Jayasree & Warwick, 1977) Kovalyev & Tchesunov, 2005 (additional source)
Calomicrolaimus honestus (de Man, 1922) Jensen, 1978 accepted as Microlaimus honestus De Man, 1922 (additional source)
Calomicrolaimus parahonestus (Gerlach, 1950) Jensen, 1978 accepted as Microlaimus parahonestus Gerlach, 1950 (additional source)
Calomicrolaimus spirifer (Warwick, 1970) Jensen, 1978 accepted as Microlaimus spirifer Warwick, 1970 accepted as Molgolaimus spirifer (Warwick, 1970) Shi & Xu, 2017 (basis of record)
Calyptronema Marion, 1870 (additional source)
Calyptronema maxweberi (de Man, 1922) (additional source)
Camacolaiminae Micoletzky, 1924 (additional source)
Camacolaimus barbatus Warwick, 1970 accepted as Deontolaimus tardus (de Man, 1889) Holovachov & Boström, 2015 (additional source)
Camacolaimus longicauda de Man, 1922 accepted as Deontolaimus longicauda (de Man, 1922) Holovachov & Boström, 2015 (additional source)
Camacolaimus tardus de Man, 1889 accepted as Deontolaimus tardus (de Man, 1889) Holovachov & Boström, 2015 (additional source)
Campylaimus Cobb, 1920 (additional source)
Campylaimus lefeverei Gerlach, 1956 (additional source)
Ceramonema Cobb, 1920 (additional source)
Ceramonema yunfengi Platt & Zhang, 1982 (additional source)
Ceramonematidae Cobb, 1933 (additional source)
Chaetonema Filipjev, 1927 (additional source)
Chaetonema riemanni Platt, 1973 (additional source)
Chaetonematinae Gerlach & Riemann, 1974 (additional source)
Chitwoodia Gerlach, 1956 (additional source)
Chitwoodia tripapillata Jayasree, 1976 (additional source)
Chitwoodia warwicki Jayasree, 1976 (additional source)
Choanolaimus de Man, 1880 (additional source)
Choanolaimus psammophilus de Man, 1880 (additional source)
Choniolaimus Ditlevsen, 1918 (additional source)
Choniolaimus panicus Gerlach, 1956 (additional source)
Choniolaimus papillatus Ditlevsen, 1918 (additional source)
Chromadora Bastian, 1865 (additional source)
Chromadora macrolaima de Man, 1889 (additional source)
Chromadora nudicapitata Bastian, 1865 (additional source)
Chromadorella duopapillata Platt, 1973 (additional source)
Chromadorella filiformis (Bastian, 1865) Filipjev, 1918 (additional source)
Chromadorella parapoecilosoma (Micoletzky, 1922) Wieser, 1951 (additional source)
Chromadoridae Filipjev, 1917 (additional source)
Chromadorina (additional source)
Chromadorina Filipjev, 1918 (additional source)
Chromadorina cervix (Wieser, 1951) Wieser, 1954 (additional source)
Chromadorina germanica (Bütschli, 1874) Wieser, 1954 (additional source)
Chromadorina granulopigmentata (Wieser, 1951) Wieser, 1954 (additional source)
Chromadorinae Filipjev, 1917 (additional source)
Chromadorita Filipjev, 1922 (additional source)
Chromadorita nana Lorenzen, 1973 (additional source)
Chromadorita tenuis (G. Schneider, 1906) Filipjev, 1922 (additional source)
Chromadoroidea Filipjev, 1917 (additional source)
Chromadoropsis Filipjev, 1918 (basis of record)
Chromadoropsis vivipara (de Man, 1907) Allgen, 1928 (basis of record)
Chromaspirina inglisi Warwick, 1970 (additional source)
Chromaspirina multipapillata Jayasree & Warwick, 1977 (additional source)
Chromaspirina parapontica Luc & De Coninck, 1959 (additional source)
Cobbia de Man, 1907 (additional source)
Cobbia caledonia Warwick & Platt, 1973 (additional source)
Cobbia trefusiaeformis de Man, 1907 (additional source)
Comesomatidae Filipjev, 1918 (additional source)