Acalyptus Duméril, 1853 accepted as Acalyptophis Boulenger, 1896 (extant flag source)
Acanthia Fabricius, 1775 accepted as Cimex Linnaeus, 1758 (extant flag source)
Acanthogyrys (extant flag source)
Acanthoscelis Dietz, 1897 accepted as Acanthoscelidius (extant flag source)
Acanthostomum Looss, 1899 (extant flag source)
Acoma Steiner, 1920 accepted as Nemacoma Hope & Murphy, 1972 (extant flag source)
Acrocentropus Betten, 1934 (extant flag source)
Acronopsyche Banks, 1930 (extant flag source)
Actinocoris Reuter, 1878 (extant flag source)
Acysta Champion, 1898 (extant flag source)
Adonis Gronow in Gray, 1854 accepted as Blennius Linnaeus, 1758 (extant flag source)
Aerope Jeffreys, 1876 (extant flag source)
Afropava accepted as Afropavo Chapin, 1936 (extant flag source)
Agalliastes Fieber, 1858 (extant flag source)
Alcyonella Lamarck, 1816 (extant flag source)
Alcyonidium auct. accepted as Alcyonium Linnaeus, 1758 (extant flag source)
Alepomyia Banks, 1908 (extant flag source)
Algonquina Banks, 1916 (extant flag source)
Alicia Thomson, 1864 accepted as Egalicia Lane, 1974 (extant flag source)
Allomimus Leconte, 1876 accepted as Caulophilus Wollaston, 1854 (extant flag source)
Allosetodes Banks, 1931 (extant flag source)
Alycodes Dietz, 1891 accepted as Dorytomus Germar, 1817 (extant flag source)
Amblyphrynus Cochran & Goin, 1961 (extant flag source)
Ambyostoma accepted as Ambystoma Tschudi, 1838 (extant flag source)
Amicula Witkowski, Lange-Bertalot & Metzeltin, 2000 (extant flag source)
Amnesia Horn in Leconte, 1876 accepted as Dyslobus Leconte, 1869 (extant flag source)
Amphodus Peters, 1872 (extant flag source)
Amycus Stål, 1855 (extant flag source)
Anabolina Banks, 1903 (extant flag source)
Anacentrus Casey, 1920 accepted as Oligolochus Casey, 1892 (extant flag source)
Anatis accepted as Antalis H. Adams & A. Adams, 1854 (extant flag source)
Anaxonchiym accepted as Anaxonchium Cobb, 1920 accepted as Pomponema Cobb, 1917 (extant flag source)
Anchodemus Leconte, 1876 accepted as Listronotus Jekel, 1865 (extant flag source)
Anculopus Van Dyke, 1927 accepted as Dioptrophorus Faust, 1892 (extant flag source)
Anisodon Rosen, 1905 (extant flag source)
Ankyroderma Ludwig, 1890 accepted as Molpadia Cuvier, 1817 (extant flag source)
Anoura Gervais, 1843 accepted as Neanura Macgillivray, 1893 (extant flag source)
Anplostoma (extant flag source)
Anquinella (extant flag source)
Anthraconema Strassen, 1904 accepted as Siphonolaimus de Man, 1893 (extant flag source)
Anticyra Curtis, 1834 (extant flag source)
Antroselatus (extant flag source)
Anura Nicolet, 1847 accepted as Neanura Macgillivray, 1893 (extant flag source)
Anuridella Willem, 1906 (extant flag source)
Aphelocheira Stephens, 1836 (extant flag source)
Aphid (extant flag source)
Aphorura Macgillivray, 1893 (extant flag source)
Aphropsyche Ross, 1941 (extant flag source)
Aplonas accepted as Aplonis Gould, 1836 (extant flag source)
Apona Adanson, 1763 accepted as Lemanea Bory de Saint-Vincent, 1808 (extant flag source)
Aprion Audinet-Serville, 1838 (extant flag source)
Aramigus Horn in Leconte, 1876 (extant flag source)
Aratus Howard, 1897 (extant flag source)
Arbudas Moore in Hewitson & Moore, 1879 (extant flag source)
Arcadopsyche Banks, 1930 (extant flag source)
Arcrophanes accepted as Acrophanes Ehrenberg, 1859 accepted as Milnesium Doyère, 1840 (extant flag source)
Arctiscon Schrank, 1803 accepted as Milnesium Doyère, 1840 (extant flag source)
Arctocorixa Van Duzee, 1917 (extant flag source)
Arctoecia McLachlan, 1875 (extant flag source)
Argyreus Heckel in Russegger, 1843 accepted as Rhinichthys Agassiz, 1849 (extant flag source)
Asellus Valenciennes, 1838 accepted as Mora Risso, 1827 (extant flag source)
Asopus Burmeister in Silbermann, 1834 (extant flag source)
Aspidites Berlese & Leonardi, 1896 (extant flag source)
Aspilus Gray, 1864 (extant flag source)
Astemma Lepeletier & Serville, 1825 (extant flag source)
Asterococcus Borrel, Dujardin-Beaumetz, Jeantet & Jouan, 1910 (extant flag source)
Astrogordius Döderlein, 1911 (extant flag source)
Astroplectron (extant flag source)
Asynonychus Crotch, 1867 accepted as Naupactus Dejean, 1821 accepted as Naupactus Klug, 1829 (extant flag source)
Atherurus Blume, 1837 accepted as Pinellia Tenore, 1839 (extant flag source)
Atomyia Banks, 1905 (extant flag source)
Atoperla Banks, 1905 accepted as Perlinella Banks, 1900 (extant flag source)
Atypus Günther, 1860 accepted as Atypichthys Günther, 1862 (extant flag source)
Audinetia Ellenrieder, 1862 accepted as Andrallus Bergroth, 1905 (extant flag source)
Australochorema Schmid, 1955 (extant flag source)
Axiognathus Thomas, 1966 accepted as Amphipholis Ljungman, 1866 (extant flag source)
Bacterium accepted as Halobacterium Elazari-Volcani, 1957 (Approved Lists, 1980) (extant flag source)
Bactrophora J.G. Agardh, 1882 accepted as Cladosiphon Kützing, 1843 (extant flag source)
Baileya Kützing, 1857 accepted as Tuomeya Harvey, 1858 (extant flag source)
Balfouria Dschunkowsky, 1937 (extant flag source)
Barbourina Amaral, 1924 (extant flag source)
Baridius Schönherr, 1825 accepted as Baris Germar, 1817 (extant flag source)
Bartlettia Gray, 1871 (extant flag source)
Basanitia Ribeiro, 1922 (extant flag source)
Basiliochiton Berry, 1918 (extant flag source)
Bassus Fabricius, 1805 (extant flag source)
Batis Bonaparte, 1838 accepted as Raja Linnaeus, 1758 (extant flag source)
Belonia Kirby, 1889 (extant flag source)
Benacus Stål, 1861 (extant flag source)
Beosus Amyot & Serville, 1843 (extant flag source)
Bernardia Ashmead, 1891 (extant flag source)
Berrya Hoyle, 1939 accepted as Danoctopus Joubin, 1933 (extant flag source)
Beta Dillon & Dillon, 1945 accepted as Pseudobeta Zajciw, 1972 (extant flag source)
Bhawania accepted as Bhavania Hora, 1920 (extant flag source)
Biacanthella Scott, 1961 (extant flag source)
Bienna (extant flag source)
Blasturus Eaton, 1881 accepted as Leptophlebia Westwood, 1840 (extant flag source)
Bognenia Allgén, 1932 (extant flag source)
Bolbolaimus Cobb, 1920 (extant flag source)
Borophloeus Wollaston, 1873 (extant flag source)