Stratigraphic time - taxa
genus Abies Mill. - fir (Hauterivian - recent)
subfamily Abietoideae Lindl. Emend Pilger & Melchior (Hauterivian - recent)
genus Acanthopholis Huxley, 1867 (Lower Cretaceous)
species Acanthopholis horrida Huxley, 1867 (Lower Cretaceous)
species Acanthorhynchia parva Nekvasilová, 1975 (Lower Cretaceous)
infraorder Achelata Scholtz & Richter, 1995 (Lower Triassic - recent)
species Acinacodus tagaricus Lopatin, Maschenko & Averianov, 2010 (Lower Cretaceous)
species Acocephalites breddini Meunier, 1904 (Barremian)
superorder Actinistia (Middle Devonian - recent)
class Actinopterygii Klein, 1885 - ray-finned fishes (Upper Silurian - recent)
suborder Adephaga Schellenberg, 1806 (Hettangian - recent)
family Aegialodontidae Kermack, 1967 (Lower Cretaceous)
genus Aigialosuchus Persson, 1960 (Cretaceous)
genus Alavaraphidia Pérez-de la Fuente, Peñalver, Delclòs & Engel, 2012 (Lower Cretaceous)
species Alavaraphidia imperterrita Pérez-de la Fuente, Peñalver, Delclòs & Engel, 2012 (Lower Cretaceous)
subfamily Aleuropteryginae (Callovian - recent)
order Ambiortiformes Kuročkin, 1982 (Lower Cretaceous)
family Amiidae Bonaparte, 1831 - bowfins (Upper Jurassic - recent)
order Amiiformes Hay, 1929 - bowfins (Lower Triassic - recent)
kingdom Amoebozoa Lühe, 1913 emend. Cavalier-Smith, 1998 (Neoproterozoic - recent)
subfamily Anaidinae Nikolajev, 1996 (Lower Cretaceous - recent)
species Ancyloceras renauxianus d'Orbigny, 1842 (Cretaceous)
family Aniliidae Stejneger, 1907 - cylinder snakes (Cretaceous - recent)
suborder Anisoneura Lioy, 1864 (Upper Triassic - recent)
infraorder Anisopodomorpha Tuomikoski, 1961 (Upper Triassic - recent)
genus Anoplosaurus Seeley, 1879 (Lower Cretaceous)
species Anoplosaurus curtonotus Seeley, 1879 (Lower Cretaceous)
family Anthribidae Billberg, 1820 - fungus weevils (Middle Jurassic - recent)
suborder Apocrita Gerstäcker, 1867 (Berriasian - recent)
infraclass Apoda Oppel, 1810 (Lower Jurassic - recent)
family Araucariaceae Henkel & Hochst. (Oxfordian - recent)
family Arbaciidae Gray, 1855 (Lower Cretaceous - recent)
genus Archaefructus Sun, Dilcher, Zheng & Zhou (Lower Cretaceous)
genus Archaeodraena Jäch & Yamamoto, 2017 (Cretaceous)
species Archaeodraena cretacea Jäch & Yamamoto, 2017 (Cretaceous)
genus Archaeogryllotalpoides Martins-Neto, 1991 (Lower Cretaceous)
species Archaeogryllotalpoides ornatus Martins-Neto, 1991 (Lower Cretaceous)
superorder Archosauria (Lopingian - recent)
cohors Archosauromorpha Huene, 1946 (Lopingian - recent)
suborder Archostemata Kolbe, 1908 (Upper Triassic - recent)
genus Armanopimpla Kopylov, 2010 (Cretaceous)
phylum Arthropoda Gravenhorst, 1843 - arthropods (Cambrian - recent)
infraorder Asilomorpha Rohdendorf, 1961 (Callovian - recent)
family Astacidae Latreille, 1802 - crayfishes (Upper Jurassic - recent)
infraorder Astacidea Latreille, 1802 (Lower Jurassic - recent)
superfamily Astacoidea Latreille, 1802 - Crayfishes (Upper Jurassic - recent)
class Asteroidea De Blainville, 1830 (Lower Ordovician - recent)
genus Atlascopcosaurus Rich & Vickers-Rich, 1989 (Lower Cretaceous)
species Atlascopcosaurus loadsi Rich & Vickers-Rich, 1989 (Lower Cretaceous)
suborder Auchenorrhyncha Duméril, 1806 - cicadas and leafhoppers (Artinskian - recent)
species Austropotamobius llopisi (Via, 1971) (Barremian)
class Aves Linnaeus, 1758 - birds (Upper Jurassic - recent)
genus Avitortor Ponomarenko, 1977 (Lower Cretaceous)
species Avitortor dolchiodactylus Nikolajev, 2007 (Lower Cretaceous)
species Avitortor leptoscelis (Nikritin, 1977) (Lower Cretaceous)
species Avitortor ovalis Nikolajev, 2007 (Lower Cretaceous)
species Avitortor parallelus Nikolajev, 2007 (Lower Cretaceous)
species Avitortor primitivus Ponomarenko, 1977 (Lower Cretaceous)
subfamily Avitortorinae Nikolajev, 2007 (Lower Cretaceous)
genus Baissomantis Gratshev & Zherikhin, 1994 (Lower Cretaceous)
genus Banoberotha Whalley, 1980 (Barremian)
species Belemnobatis variabilis Underwood & Rees, 2002 (Berriasian - recent)
family Belostomatidae Leach, 1815 - toe biters (Callovian - recent)
family Berothidae Handlirsch, 1906 - Beaded lacewings (Oxfordian - recent)
family Bibionidae Fleming, 1821 - march flies (Lower Cretaceous - recent)
superfamily Bibionoidea Fleming, 1821 (Lower Cretaceous - recent)
infraorder Bibionomorpha Hennig, 1954 (Berriasian - recent)
subfamily Bittacomorphinae (Hauterivian - recent)
family Blephariceridae Schiner, 1862 - Net-winged midges (Callovian - recent)
superfamily Blephariceroidea Brues & Melander, 1932 (Callovian - recent)
infraorder Blephariceromorpha Rohdendorf, 1961 (Callovian - recent)
species Bohemirhynchia soukupi Nekvasilova, 1973 (Cretaceous)
subfamily Bolboceratinae Mulsant, 1842 (Lower Cretaceous - recent)