ARMS Taxon list
"Lower Heterobranchia"
Aartsenia Warén, 1991
Aartsenia candida (Møller, 1842)
Aberrantospermata Jondelius, Wallberg, Hooge & Raikova, 2011
Abietinaria Kirchenpauer, 1884
Abietinaria abietina (Linnaeus, 1758)
Abietinaria filicula (Ellis & Solander, 1786)
Abietinaria fusca (Johnston, 1847)
Abietinaria pulchra (Nutting, 1904)
Abietinaria thuiarioides (Clark, 1877)
Abietinaria turgida (Clark, 1877)
Abludomelita Karaman, 1981
Abludomelita valida (Shoemaker, 1955) accepted as Melitoides valida (Shoemaker, 1955)
Abyssidrilus Erséus, 1992
Abyssidrilus altus (Erséus, 1980)
Abyssoninoe Orensanz, 1990
Abyssoninoe hibernica (McIntosh, 1903)
Abyssoninoe scopa (Fauchald, 1974)
Acanthephyridae Spence Bate, 1888
Acanthocardia J. E. Gray, 1851
Acanthocardia echinata (Linnaeus, 1758)
Acanthocardiini Kafanov & Starobogatov, 1977
Acanthochitonina
Acanthocyclops Kiefer, 1927
Acanthocyclops vernalis (Fischer, 1853) represented as Acanthocyclops vernalis vernalis (Fischer, 1853)
Acanthocyclops vernalis vernalis (Fischer, 1853)
Acanthocythereis Howe, 1963
Acanthocythereis agapensis Lev, 1983
Acanthocythereis dunelmensis (Norman, 1865) accepted as Actinocythereis dunelmensis (Norman, 1865)
Acanthodasys Remane, 1927
Acanthodasys aculeatus Remane, 1927
Acanthodoris J. E. Gray, 1850
Acanthodoris pilosa (Abildgaard, 1789)
Acantholaimus Allgén, 1933
Acantholaimus ewensis Platt & Zhang, 1982 accepted as Acantholaimus polydentatus Gerlach, 1951
Acantholaimus polydentatus Gerlach, 1951
Acantholumpenus Makushok, 1958
Acantholumpenus mackayi (Gilbert, 1896)
Acanthomysis Czerniavsky, 1882
Acanthomysis dybowskii (Derzhavin, 1913) accepted as Disacanthomysis dybowskii (Derzhavin, 1913)
Acanthomysis stelleri (Derzhavin, 1913)
Acanthonotozoma Boeck, 1876
Acanthonotozoma cristatum (Ross, 1835)
Acanthonotozoma dunbari Just, 1978
Acanthonotozoma gurjanovae Just, 1978
Acanthonotozoma inflatum (Krøyer, 1842)
Acanthonotozoma magnum Just, 1978
Acanthonotozoma monodentatum Kudrjaschov, 1965
Acanthonotozoma rusanovae Bryazgin, 1974
Acanthonotozoma serratum (O. Fabricius, 1780)
Acanthonotozoma sinuatum Just, 1978
Acanthonotozomatidae Stebbing, 1906
Acanthopsetta Schmidt, 1904
Acanthopsetta nadeshnyi Schmidt, 1904
Acanthostega
Acanthostegomorpha
Acanthostepheia Boeck, 1871
Acanthostepheia behringiensis (Lockington, 1877)
Acanthostepheia incarinata Gurjanova, 1929
Acanthostepheia malmgreni (Goës, 1866)
Acanthostomella Jörgensen, 1927
Acanthostomella norvegica (Daday, 1887)
Acanthozone Boeck, 1871 accepted as Paramphithoe Bruzelius, 1859
Acanthozone polyacantha Murdoch, 1885 accepted as Paramphithoe polyacantha (Murdoch, 1885)
Acari
Acariformes
Acarina accepted as Acari
Acarnidae Dendy, 1922
Acartia Dana, 1846
Acartia (Acanthacartia) Steuer, 1915
Acartia (Acanthacartia) bifilosa (Giesbrecht, 1881)
Acartia (Acanthacartia) tumida Willey, 1920
Acartia (Acartiura) Steuer, 1915
Acartia (Acartiura) clausi Giesbrecht, 1889
Acartia (Acartiura) hudsonica Pinhey, 1926
Acartia (Acartiura) longiremis (Lilljeborg, 1853)
Acartiidae Sars G.O., 1903
Acaulidae Fraser, 1924
Acaulis Stimpson, 1853
Acaulis primarius Stimpson, 1853
Aceroides G.O. Sars, 1892
Aceroides (Aceroides) G.O. Sars, 1892
Aceroides (Aceroides) latipes (G.O. Sars, 1883)
Aceroides (Aceroides) latipes latipes (G.O. Sars, 1883) represented as Aceroides (Aceroides) latipes (G.O. Sars, 1883)
Aceroides (Aceroides) latipes robusta Gurjanova, 1933
Aceroides (Aceroides) sedovi Gurjanova, 1946
Acervulinoidea Schultze, 1854
Acetabulastoma Schornikov, 1970
Acetabulastoma arcticum Schornikov, 1970
Acetabulastoma hyperboreum (Scott, 1899)
Acetabulastoma rostratum (Sars, 1866)
Achelia Hodge, 1864
Achelia alaskensis (Cole, 1904)
Achelia borealis (Schimkewitsch, 1895)
Achelia echinata Hodge, 1864
Achelia laevis Hodge, 1864
Achelia lavrentii (Losina-Losinsky, L.K., 1933) accepted as Achelia spinosa (Stimpson, 1853)
Achelia litke (Losina-Losinsky, L.K., 1933) accepted as Achelia spinosa (Stimpson, 1853)
Achelia salebrosa Losina-Losinsky, 1961
Achelia spinosa (Stimpson, 1853)