Ablutomelita obtusata – synonym of Abludomelita obtusata
Acanthocaris livingstoneana Sim, 1872 – synonym of Gastrosaccus spinifer
Acanthonotus guttatus Costa, 1851 – synonym of Atylus guttatus
Acanthonotus owenii Bate, 1857 – synonym of Epimeria cornigera
Acanthonotus testudo White, 1850 – synonym of Epimeria cornigera
Aceros phyllonyx Boeck, 1871 – synonym of Arrhis phyllonyx
Acidostoma laticorne Chevreux and Fage, 1925 – synonym of Acidostoma obesum
Acidostoma neglectum Dahl, 1964 – synonym of Acidostoma obesum
Acidostoma obesum Auct. non Bate and Westwood, 1861 – synonym of Acidostoma nodiferum
Acidostoma sarsi Lincoln, 1979 – synonym of Acidostoma nodiferum
Aega affinis H. Milne-Edwards, 1840 – synonym of Aega psora
Aega emarginata Leach, 1815 – synonym of Aega psora
Aega lovéni Bovallius – synonym of Aega ventrosa
Aegiochus nordenskjöldi Bovallius – synonym of Aega ventrosa
Aegiochus ventrosus Bovallius – synonym of Aega ventrosa
Alauna rostrata Goodsir, 1843 – synonym of Diastylis laevis
Albunea dentata Fabricius, 1798 – synonym of Corystes cassivelaunus
Allorchestes imbricatus Bate, 1857 – synonym of Hyale pontica
Allorchestes nilssonii Bate and Westwood, 1861 – synonym of Hyale prevosti
Alphaeus polaris Sabine, 1824 – synonym of Lebbeus polaris
Amathilla homari Stebbing, 1888 – synonym of Gammarellus homari
Ampelisca belliana Bate and Westwood, 1861 – synonym of Ampelisca brevicornis
Ampelisca gaimardii Bate and Westwood, 1861 – synonym of Ampelisca typica
Ampelisca gaimardii Kröyer, 1846 – synonym of Byblis gaimardi
Ampelisca laevigata Bate, 1862 – synonym of Ampelisca tenuicornis
Ampelisca laevigata Sars, 1891 – synonym of Ampelisca brevicornis
Amphilochoides boeckii Sars, 1892 – synonym of Amphilochoides boecki
Amphilochoides intermedius Scott, 1896 – synonym of Paramphilochoides intermedius
Amphilochoides odontonyx Sars, 1892 – synonym of Amphilochoides boecki
Amphilochoides odontonyx Sars, 1895 – synonym of Paramphilochoides odontonyx
Amphilochoides pusillus Boeck, 1871 – synonym of Paramphilochoides odontonyx
Amphilochus anomalus Chevreux, 1900 – synonym of Amphilochus spencebatei
Amphilochus bispinosus Boeck, 1871 – synonym of Gitanopsis bispinosa
Amphilochus brunneus Della Valle, 1893 – synonym of Amphilochus spencebatei
Amphilochus odontonyx Boeck, 1871 – synonym of Paramphilochoides odontonyx
Amphilochus sabrinae Stebbing, 1878 – synonym of Gitana sarsi
Amphithoe bicuspis Kroyer, 1838a – synonym of Parapleustes bicuspis
Amphithoe jurinei Milne-Edwards, 1830 – synonym of Apherusa jurinei
Amphithoe laeviuscula Kröyer, 1838 – synonym of Calliopius laeviusculus
Amphithoe littorina Bate, 1857 – synonym of Ampithoe rubricata
Amphithoe nilssonii Rathke, 1843 – synonym of Hyale prevosti
Amphithoe norvegica Rathke, 1843 – synonym of Apherusa jurinei
Amphithoe obtusata Milne-Edwards, 1830 – synonym of Abludomelita obtusata
Amphithoe parasitica M. Sars, 1859 – synonym of Epimeria parasitica
Amphithoe pelagica Milne-Edwards, 1830 – synonym of Sunamphitoe pelagica
Amphithoe pontica Milne-Edwards, 1840 – synonym of Hyale pontica
Amphithoe prevostii Milne-Edwards, 1830 – synonym of Hyale prevosti
Amphithoe rubricata Bate, 1862 – synonym of Ampithoe rubricata
Amphithoe swammerdamei Milne-Edwards, 1830 – synonym of Atylus swammerdami
Amphithopsis nodifera Sars, 1882 – synonym of Stenopleustes nodifer
Anapagurus brevicarpus A. Milne Edwards & Bouvier, 1892 – synonym of Anapagurus chiroacanthus
Anapagurus chiracanthus Balss, 1924 – synonym of Anapagurus chiroacanthus
Anapagurus chiroacanthus var. cristatus Fenizia, 1937 – synonym of Anapagurus chiroacanthus
Anapagurus chiroacanthus var. gracilis Fenizia, 1937 – synonym of Anapagurus chiroacanthus
Anapagurus curvidactylus A. Milne Edwards and Bouvier, 1892 – synonym of Anapagurus hyndmanni
Anapagurus hyndmani Gurney, 1942 – synonym of Anapagurus hyndmanni
Anapagurus hyndmanni Bouvier, 1891 – synonym of Anapagurus hyndmanni
Anceus manticorus Hesse – synonym of Gnathia maxillaris
Anceus maxillaris Lamk. – synonym of Gnathia maxillaris
Anceus oxyuraeus Lilljeborg – synonym of Gnathia maxillaris
Anchialina mediterranea Colosi, 1922 – synonym of Anchialina agilis
Anonyx cicada Stebbing, 1888 – synonym of Tmetonyx cicada
Anonyx denticulata Bate, 1857 – synonym of Hippomedon denticulatus
Anonyx edwardsi Bate, 1857 – synonym of Orchomene humilis
Anonyx nanoides Lilljeborg, 1865 – synonym of Tryphosella nanoides
Anonyx nanus Kroyer, 1846 – synonym of Orchomene nanus
Anonyx obesus Bate and Westwood, 1861 – synonym of Acidostoma obesum
Anonyx obtusifrons Boeck, 1861 – synonym of Menigrates obtusifrons
Anthura carinata Krøyer, 1848 – synonym of Cyathura carinata
Anthura gracilis Dahl, 1916 – synonym of Cyathura carinata
Apherusa borealis Sars, 1893 – synonym of Apherusa cirrus
Apherusa clevei Reibisch, 1906 – synonym of Apherusa ovalipes
Apseudes hibernicus Walker, 1897 – synonym of Apseudes talpa
Apseudes latreillii Bate and Westwood, 1868 – synonym of Apseudes latreillii
Araneops brevicornis Costa, 1853 – synonym of Ampelisca brevicornis
Argissa typica Boeck, 1871 – synonym of Argissa hamatipes
Asellus aquaticus cracoviensis Kulczycki, 1885 – synonym of Asellus aquaticus
Asellus arthrobranchialis Dudich, 1925 – synonym of Asellus aquaticus
Asellus goplanus Kulczycki, 1885 – synonym of Asellus aquaticus
Asellus goplanus switesiana Kulczycki, 1885 – synonym of Asellus aquaticus
Asellus vulgaris Latreille, 1803 – synonym of Asellus aquaticus
Astacus harengum Fabricius, 1778 – synonym of Praunus flexuosus
Astacus homari Fabricius, 1779 – synonym of Gammarellus homari
Atelecyclus heterodon Leach, 1815 – synonym of Atelecyclus rotundatus
Atelecyclus septemdentatus White, 1857 – synonym of Atelecyclus rotundatus
Atylus compressus Bate, 1862 – synonym of Atylus swammerdami
Atylus macer Norman, 1869 – synonym of Melphidippella macra
Audouinia acherusica Costa, 1851 – synonym of Corophium acherusicum
Autonoe anomala Bruzelius, 1859 – synonym of Microdeutopus anomalus
Autonoe grandimana Bruzelius, 1859 – synonym of Microdeutopus gryllotalpa
Autonoe versiculata Norman, 1886 – synonym of Microdeutopus versiculatus
Autonoe websteri Sars, 1894 – synonym of Lembos websteri