| Acanaloniidae Amyot and Se..., 1843 | Acanalonid planthoppers | 38 | Species | Taxom |
| Acanthopidae Burmeister, 1838 | | 17 | Species | Taxom |
| Acanthopteroctetidae Davis, 1978 | Archaic Sun Moths | 4 | Species | Taxom |
| Acanthosomatidae Signoret, 1864 | Acanthosomatids | 9 | Species | Taxom |
| Acartophthalmidae Czerny, 1928 | Acartophthalmid flies | 3 | Species | Taxom |
| Achilidae Stål, 1866 | Achilid Planthoppers | 102 | Species | Taxom |
| Aclerdidae Ferris, 1937 | Aclerdid scales | 24 | Species | Taxom |
| Acmaeoblattidae Durden, 1969 | | 3 | Species | Taxom |
| Acrididae MacLeay, 1819 | Grasshoppers and locusts | 1332 | Species | Taxom |
| Acroceridae Leach, 1815 | Hunch-back flies | 101 | Species | Taxom |
| Adelgidae Heinze, 1962 | Adelgids | 33 | Species | Taxom |
| Adelidae Bruand, 1851 | Adelid Moths | 52 | Species | Taxom |
| Adeloblattidae Durden, 1969 | | 4 | Species | Taxom |
| Adeloneuridae Carpenter, 1938 | | 1 | Species | Taxom |
| Ademosynidae Ponomarenko, 1968 | | 1 | Species | Taxom |
| Aderidae Winkler, 1927 | Ant-like leaf beetles | 92 | Species | Taxom |
| Adiheterothripidae Shumsher, 1946 | | 2 | Species | Taxom |
| Aenictopecheidae Usinger, 1932 | | 1 | Species | Taxom |
| Aeolothripidae Uzel, 1895 | Banded thrips | 73 | Species | Taxom |
| Aerophasmidae Martynov, 1928 | | 1 | Species | Taxom |
| Aeshnidae Rambur, 1842 | Darners | 113 | Species | Taxom |
| Aetalionidae Spinola, 1850 | Treehopper | 4 | Species | Taxom |
| Agaonidae Walker, 1848 | Fig wasp | 52 | Species | Taxom |
| Agathemeridae Bradler, 2003 | | 1 | Species | Taxom |
| Agonoxenidae (Meyrick, 1926) | Palm Moths | 1 | Species | Taxom |
| Agromyzidae Fallen, 1823 | Leaf miner flies | 1298 | Species | Taxom |
| Agyrtidae Thomson, 1859 | Primitive carrion beetles | 22 | Species | Taxom |
| Aididae Schaus, 1906 | | 3 | Species | Taxom |
| Alexiidae Imhoff, 1856 | Minute bark beetles | 2 | Species | Taxom |
| Aleyrodidae Westwood, 1840 | Whiteflies | 248 | Species | Taxom |
| Alinkidae Krzemi& 324;ski, 1992 | | 1 | Species | Taxom |
| Alucitidae Leach, 1815 | Many Plumed Moths | 17 | Species | Taxom |
| Alydidae Amyot & Serv..., 1843 | Bean bugs | 67 | Species | Taxom |
| Ambermantidae Grimaldi, 2003 | | 1 | Species | Taxom |
| Ambloblattidae Durden, 1969 | | 1 | Species | Taxom |
| Amboneuridae Carpenter, 1980 | | 1 | Species | Taxom |
| Ametropodidae Bengtsson, 1913 | Sand minnow mayflies | 5 | Species | Taxom |
| Amorphoscelidae Stål, 1877 | | 2 | Species | Taxom |
| Amphientomidae Enderlein, 1903 | Tropical Barklice | 6 | Species | Taxom |
| Amphipsocidae Mockford, 1978 | Hairy-winged Barklice | 3 | Species | Taxom |
| Amphipterygidae Selys, 1853 | | 4 | Species | Taxom |
| Amphizoidae LeConte, 1853 | Stout-stream beetles | 3 | Species | Taxom |
| Ampulicidae Shuckard, 1840 | Ampulicid wasps | 10 | Species | Taxom |
| Anaxyelidae Martynov, 1925 | Anaxyelids | 2 | Species | Taxom |
| Ancopteridae Kukalova-Peck, 1975 | | 1 | Species | Taxom |
| Andrenidae Webster, 1913 | Andrenid bees | 1577 | Species | Taxom |
| Anelcanidae Carpenter, 1986 | | 2 | Species | Taxom |
| Angarosphecidae Rasnitsyn, 1975 | | 1 | Species | Taxom |
| Anisembiidae Davis, 1940 | | 44 | Species | Taxom |
| Anisolabididae Verhoeff, 1902 | | 8 | Species | Taxom |
| Anisopodidae Knab, 1912 | Window Midges | 25 | Species | Taxom |
| Anomalogrammatidae Carpenter, 1943 | | 1 | Species | Taxom |
| Anomalopsychidae Flint, 1981 | | 1 | Species | Taxom |
| Anormochoristidae Tillyard, 1926 | | 1 | Species | Taxom |
| Anostostomatidae Saussure, 1859 | Wetas & King Crickets | 25 | Species | Taxom |
| Antemylacridae Durden, 1972 | | 1 | Species | Taxom |
| Anthelidae Turner, 1904 | Australian Lappet Moths | 4 | Species | Taxom |
| Anthicidae Latreille, 1819 | Ant beetles | 477 | Species | Taxom |
| Anthocoridae Fieber, 1837 | Flower bugs | 140 | Species | Taxom |
| Anthomyiidae Robineau-Des..., 1830 | Anthomyiid flies | 1020 | Species | Taxom |
| Anthomyzidae Czerny, 1903 | Anthomyzid flies | 44 | Species | Taxom |
| Anthophoridae (C. L. Koch, 1846) | | 9 | Species | Taxom |
| Anthracoblattinidae Durden, 1969 | | 9 | Species | Taxom |
| Anthracoptilidae Handlirsch, 1922 | | 1 | Species | Taxom |
| Anthracothremmidae Handlirsch, 1906 | | 2 | Species | Taxom |
| Anthribidae Billberg, 1820 | Fungus Weevil | 309 | Species | Taxom |
| Apataniidae Wallengren, 1886 | Early Smoky Wing Sedges | 36 | Species | Taxom |
| Apatelodidae Neumoegen & ..., 1894 | American Silkworm Moths | 2 | Species | Taxom |
| Aphalaridae Löw, 1879 | | 122 | Species | Taxom |
| Aphelinidae Thomson, 1876 | Aphelinid wasps | 297 | Species | Taxom |
| Apheloneuridae Carpenter, 1976 | | 2 | Species | Taxom |
| Aphididae Latreille, 1802 | Aphid | 1966 | Species | Taxom |
| Aphodiidae Leach, 1815 | | 4 | Species | Taxom |
| Aphrophoridae Evans, 1946 | Froghoppers | 69 | Species | Taxom |
| Apidae Latreille, 1802 | Bumble bees | 2137 | Species | Taxom |
| Apioceridae Bigot, 1852 | Flower-loving flies | 110 | Species | Taxom |
| Apithanidae Handlirsch, 1911 | | 1 | Species | Taxom |
| Apsidoneuridae Carpenter, 1961 | | 1 | Species | Taxom |
| Aradidae Spinola, 1837 | Flat bug | 168 | Species | Taxom |
| Archaeolepiidae Whalley, 1985 | | 1 | Species | Taxom |
| Archegocimicidae Handlirsch, 1906 | | 2 | Species | Taxom |
| Archembiidae Ross, 2001 | | 6 | Species | Taxom |
| Archeocrypticidae Kaszab, 1964 | Ancient Fungus Beetles | 5 | Species | Taxom |
| Archescytinidae Tillyard, 1926 | | 14 | Species | Taxom |
| Archilimoniidae Krzeminski &..., 2003 | | 1 | Species | Taxom |
| Archimylacridae Handlirsch, 1906 | | 88 | Species | Taxom |
| Archipsocidae Enderlein, 1903 | Ancient Barklice | 19 | Species | Taxom |
| Archizelmiridae Rohdendorf, 1962 | | 1 | Species | Taxom |
| Archoblattinidae (Schneider, 1983) | | 1 | Species | Taxom |
| Archotermopsidae Engel, Grima..., 2009 | Rottenwood Termites | 1 | Species | Taxom |
| Arctiidae Leach, 1815 | Footman moths | 108 | Species | Taxom |
| Argidae Konow, 1890 | Argid flies | 130 | Species | Taxom |
| Artematopodidae Lacordaire, 1857 | Soft bodied plant beetle | 14 | Species | Taxom |
| Artheneidae Stål, 1872 | | 2 | Species | Taxom |
| Arthropleidae Balthasar, 1937 | Flatheaded Mayflies | 1 | Species | Taxom |
| Ascalaphidae Rambur, 1842 | Owlflies | 32 | Species | Taxom |
| Aschiphasmatidae Brunner von ..., 1893 | | 3 | Species | Taxom |
| Asienthomidae (Martynov, 1926) | | 0 | Species | Taxom |
| Asilidae Latreille, 1802 | Assassin flies | 2099 | Species | Taxom |
| Asiopsocidae Mockford & G..., 1976 | | 3 | Species | Taxom |
| Asteiidae Rondani, 1856 | Asteiid Flies | 40 | Species | Taxom |
| Asterolecaniidae Cockerell, 1896 | Asterolecaniids | 44 | Species | Taxom |
| Asthenohymenidae Tillyard, 1924 | | 14 | Species | Taxom |
| Atelestidae Hennig, 1970 | | 10 | Species | Taxom |
| Athericidae Stuckenberg, 1973 | Athericid flies | 13 | Species | Taxom |
| Attelabidae Billberg, 1820 | Leaf Rolling Weevil | 454 | Species | Taxom |
| Aulacidae Shuckard, 1842 | Aulacid wasps | 51 | Species | Taxom |
| Aulacigastridae Wollaston, 1864 | Aulacigastrid flies | 4 | Species | Taxom |
| Aulertupidae Zessin & Bra..., 2010 | | 1 | Species | Taxom |
| Australiphemeridae McCafferty, 1991 | | 1 | Species | Taxom |
| Austroleptidae Nagatomi, 1982 | | 1 | Species | Taxom |
| Autostichidae Le Marchand, 1947 | Autostichid Moths | 36 | Species | Taxom |
| Awesomidae | | 1 | Species | Taxom |
| Axymyiidae Rohdendorf, 1946 | Axymyiidae flies | 2 | Species | Taxom |
| Bacillidae Brunner von ..., 1893 | Bacillid Stick Insects | 1 | Species | Taxom |
| Bacunculidae (Brunner, 1893) | | 1 | Species | Taxom |
| Baetidae Leach, 1815 | Mayflies | 288 | Species | Taxom |
| Baetiscidae Banks, 1900 | Armored Mayflies | 14 | Species | Taxom |
| Baissidae Rasnitsyn, 1975 | | 1 | Species | Taxom |
| Bardohymenidae Zalessky, 1937 | | 3 | Species | Taxom |
| Batrachedridae Heinemann & ..., 1876 | Batrachedrid Moths | 51 | Species | Taxom |
| Behningiidae Motas & Bacesco, 1937 | Tuskless burrowing mayflies | 1 | Species | Taxom |
| Belidae Schönherr, 1826 | Belid Beetle | 57 | Species | Taxom |
| Belostomatidae Leach, 1815 | Alligator ticks | 59 | Species | Taxom |
| Beraeidae Wallengren, 1891 | Small eastern caddisflies | 6 | Species | Taxom |
| Berothidae Handlirsch, 1906 | Beaded lacewing | 18 | Species | Taxom |
| Berytidae Fieber, 1851 | Stilt bug | 33 | Species | Taxom |
| Bethylidae Halliday, 1839 | Bethylid wasps | 327 | Species | Taxom |
| Biarmohymenidae Zalessky, 1937 | | 1 | Species | Taxom |
| Bibionidae Fleming, 1821 | Bibionid flies | 223 | Species | Taxom |
| Bintoniellidae Handlirsch, 1937 | | 0 | Species | Taxom |
| Biphyllidae LeConte, 1861 | Biphyllid beetles | 4 | Species | Taxom |
| Bittacidae Handlirsch, 1906 | Hanging scorpionflies | 23 | Species | Taxom |
| Blaberidae Saussure, 1864 | Blaberids | 78 | Species | Taxom |
| Blasticotomidae Thomson, 1871 | Blasticotomid sawflies | 2 | Species | Taxom |
| Blastobasidae (Meyrick, 1894) | Blastobasid moths | 16 | Species | Taxom |
| Blattellidae (Karny, 1908) | German Cockroach | 80 | Species | Taxom |
| Blattidae Stephens, 1829 | American cockroaches | 37 | Species | Taxom |
| Blattinopsidae Bolton, 1925 | | 12 | Species | Taxom |
| Blattulidae Vishnyokova, 1982 | | 3 | Species | Taxom |
| Blephariceridae Loew, 1861 | Mountain midges | 49 | Species | Taxom |
| Blissidae Stål, 1862 | Chinch Bugs | 56 | Species | Taxom |
| Bohartillidae Kinzelbach, 1969 | | 1 | Species | Taxom |
| Bolboceratidae (Mulsant, 1842) | Dor beetle | 3 | Species | Taxom |
| Bombycidae Latreille, 1802 | Lappet moths | 90 | Species | Taxom |
| Bombyliidae Latreille, 1802 | Bee Flies | 1929 | Species | Taxom |
| Boopiidae Mjöberg, 1910 | | 2 | Species | Taxom |
| Boreidae Latreille, 1816 | Snow fleas | 17 | Species | Taxom |
| Boridae C. G. Thomson, 1859 | Borids | 2 | Species | Taxom |
| Bostrichidae Latreille, 1802 | Auger beetles | 260 | Species | Taxom |
| Bothrideridae Erichson, 1845 | Cocoon-forming beetles | 19 | Species | Taxom |
| Brachodidae Agenjo, 1966 | Little Bear Moths | 4 | Species | Taxom |
| Brachonidae | | 1 | Species | Taxom |
| Brachycentridae Ulmer, 1903 | Humpless Casemaker Caddisflies | 25 | Species | Taxom |
| Brachyceridae (Billberg, 1820) | Brachycerids | 1 | Species | Taxom |
| Brachypsectridae LeConte & Horn, 1883 | Texas beetle | 1 | Species | Taxom |
| Brachypteridae (Erichson, 1845) | Short-winged Flower Beetles | 22 | Species | Taxom |
| Brachystomatidae Melander, 1908 | | 6 | Species | Taxom |
| Braconidae Latreille, 1829 | Braconid wasps | 3853 | Species | Taxom |
| Bradyblattidae Durden, 1969 | | 64 | Species | Taxom |
| Bradynobaenidae Saussure, 1892 | Bradynobaenid wasps | 51 | Species | Taxom |
| Braulidae Egger, 1853 | Bee lice | 1 | Species | Taxom |
| Brentidae Billberg, 1820 | Brenthidae | 423 | Species | Taxom |
| Breyeriidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Brodiidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Brodiopteridae Carpenter, 1963 | | 3 | Species | Taxom |
| Brongniartiellidae Martynova, 1949 | | 1 | Species | Taxom |
| Buprestidae Leach, 1815 | Flat-headed wood-borers | 1708 | Species | Taxom |
| Byrrhidae Latreille, 1804 | Moss beetles | 120 | Species | Taxom |
| Byturidae Jacquelin du..., 1858 | Fruit worms | 11 | Species | Taxom |
| Cacurgidae Handlirsch, 1911 | | 3 | Species | Taxom |
| Caeciliusidae Kolbe, 1880 | Lizard Barklice | 82 | Species | Taxom |
| Caenidae Newman, 1853 | Small square-gill mayflies | 57 | Species | Taxom |
| Calamoceratidae Ulmer, 1905 | | 14 | Species | Taxom |
| Caliscelidae Amyot & Serv..., 1843 | Piglet Bugs | 64 | Species | Taxom |
| Callaphididae (Borner, 1952) | | 9 | Species | Taxom |
| Callidulidae Moore, 1877 | Old World Butterfly Moths | 1 | Species | Taxom |
| Calliphoridae Brauer & Ber..., 1889 | Blow flies | 285 | Species | Taxom |
| Callirhipidae Emden, 1924 | Callirhipid beetles | 12 | Species | Taxom |
| Calocidae Ross, 1967 | | 2 | Species | Taxom |
| Caloneuridae Handlirsch, 1906 | | 6 | Species | Taxom |
| Calophyidae Vondracek, 1957 | | 17 | Species | Taxom |
| Calopterygidae Selys, 1850 | Broad-winged damselflies | 26 | Species | Taxom |
| Calvertiellidae Martynov, 1931 | | 4 | Species | Taxom |
| Camillidae Frey, 1921 | Camillid flies | 7 | Species | Taxom |
| Campterophlebiidae Handlirsch, 1920 | | 1 | Species | Taxom |
| Camptotaxineuridae Tillyard, 1937 | | 1 | Species | Taxom |
| Canaceidae (Jones, 1906) | Beach flies | 33 | Species | Taxom |
| Canacidae Jones, 1906 | Beach Flies | 1 | Species | Taxom |
| Canadaphididae Richards, 1966 | | 1 | Species | Taxom |
| Cantharidae Imhoff, 1856 | Cantharids | 744 | Species | Taxom |
| Canthyloscelidae Enderlein, 1912 | | 5 | Species | Taxom |
| Capniidae Klapálek, 1905 | Capniid winter stoneflies | 204 | Species | Taxom |
| Carabidae Latreille, 1802 | Carabid beetles | 6023 | Species | Taxom |
| Carcinophoridae Hincks, 1954 | | 14 | Species | Taxom |
| Caridae Thompson, 1992 | | 1 | Species | Taxom |
| Carnidae Newman, 1834 | Bird flies | 26 | Species | Taxom |
| Carposinidae Walsingham, 1907 | Carposinid moths | 31 | Species | Taxom |
| Carsidaridae Crawford, 1911 | | 6 | Species | Taxom |
| Castniidae Boisduval, 1828 | Castniid moths | 27 | Species | Taxom |
| Cecidomyiidae Newman, 1834 | Cecidomyidae | 1626 | Species | Taxom |
| Cephidae Newman, 1834 | Cephids | 22 | Species | Taxom |
| Cerambycidae Latreille, 1802 | Long Horn beetles | 4127 | Species | Taxom |
| Ceraphronidae Haliday, 1833 | Ceraphronid wasps | 65 | Species | Taxom |
| Ceratocombidae Fieber, 1861 | | 9 | Species | Taxom |
| Ceratophyllidae Dampf, 1908 | Bird Fleas | 273 | Species | Taxom |
| Ceratopogonidae Newman, 1834 | Biting midge | 963 | Species | Taxom |
| Cercopidae Leach, 1815 | Froghopper | 93 | Species | Taxom |
| Cerococcidae Balachowsky, 1942 | Cerococcids | 9 | Species | Taxom |
| Cerophytidae Latreille, 1834 | Cerophytid beetles | 5 | Species | Taxom |
| Cerylonidae Billberg, 1820 | Cerylid Kingfishers | 57 | Species | Taxom |
| Cetoniidae (Leach, 1815) | Flower beetles | 1 | Species | Taxom |
| Chalcididae Latreille, 1817 | Chalcidid wasps | 307 | Species | Taxom |
| Chamaemyiidae Hendel, 1910 | Aphid flies | 96 | Species | Taxom |
| Chaoboridae Newman, 1834 | Phantom midge | 46 | Species | Taxom |
| Cheliphlebidae Handlirsch, 1911 | | 4 | Species | Taxom |
| Chelisochidae Burr, 1907 | Black earwig | 3 | Species | Taxom |
| Chelonariidae Blanchard, 1845 | Chelonarid beetles | 11 | Species | Taxom |
| Chimabachidae (HEINEMANN, 1870) | Chimabachid Moths | 1 | Species | Taxom |
| Chironomidae Erichson, 1842 | Chironomids | 1871 | Species | Taxom |
| Chlorogomphidae Needham, 1903 | | 1 | Species | Taxom |
| Chloroperlidae Okamoto, 1912 | Green stoneflies | 148 | Species | Taxom |
| Chloropidae Schoenherr, 1840 | Chloropid flies | 519 | Species | Taxom |
| Choreutidae Stainton, 1854 | Choreuitid Moths | 71 | Species | Taxom |
| Chorotypidae Stål, 1873 | | 1 | Species | Taxom |
| Chrysididae Latreille, 1802 | Chrysidid wasps | 359 | Species | Taxom |
| Chrysomelidae Latreille, 1802 | Casebearers | 3697 | Species | Taxom |
| Chrysopidae Schneider, 1851 | And Green Lacewings | 208 | Species | Taxom |
| Chyromyidae Hendel, 1916 | Chiromyid flies | 17 | Species | Taxom |
| Cicadellidae Latreille, 1802 | Cicadellids | 7321 | Species | Taxom |
| Cicadidae Westwood, 1840 | Cicada | 425 | Species | Taxom |
| Ciidae Leach, 1819 | Minute tree fungus beetles | 182 | Species | Taxom |
| Cimbicidae Kirby, 1837 | Cimbicid sawflies | 31 | Species | Taxom |
| Cimbrophlebiidae Willmann, 1977 | Hangingfly | 4 | Species | Taxom |
| Cimicidae Latreille, 1802 | Bat bugs | 19 | Species | Taxom |
| Cixiidae Spinola, 1839 | Cixid planthoppers | 481 | Species | Taxom |
| Clambidae Fischer, 1821 | Fringe-winged beetles | 25 | Species | Taxom |
| Clastopteridae Stål, 1858 | Clastopterid Spittlebugs | 53 | Species | Taxom |
| Cleridae Latreille, 1802 | Checkered Beetle | 462 | Species | Taxom |
| Clusiidae Schönherr, 1840 | Clusiid flies | 73 | Species | Taxom |
| Cnemidolestidae Handlirsch, 1906 | | 3 | Species | Taxom |
| Cneoglossidae Champion, 1897 | | 1 | Species | Taxom |
| Cobaloblattidae Durden, 1969 | | 1 | Species | Taxom |
| Coccidae Stephens, 1829 | Soft scale | 259 | Species | Taxom |
| Coccinellidae Latreille, 1807 | Coccinelles | 803 | Species | Taxom |
| Coelopidae Hendel, 1910 | Kelp Flies | 7 | Species | Taxom |
| Coenagrionidae Kirby, 1890 | Narrow-winged damselflies | 265 | Species | Taxom |
| Coenomyiidae (Westwood, 1840) | Smell flies | 1 | Species | Taxom |
| Coleophoridae Hübner, 1825 | Case moths | 1684 | Species | Taxom |
| Colletidae Lepeletier, 1841 | Colletid bees | 414 | Species | Taxom |
| Compsocidae Mockford, 1967 | | 2 | Species | Taxom |
| Conchaspididae Green, 1896 | False armored scales | 5 | Species | Taxom |
| Coniopterygidae Burmeister, 1839 | Dusty lacewings | 78 | Species | Taxom |
| Conoesucidae Ross, 1967 | | 2 | Species | Taxom |
| Conopidae Latreille, 1802 | Thick-headed Flies | 148 | Species | Taxom |
| Copromorphidae Meyrick, 1905 | Fig Borers | 6 | Species | Taxom |
| Coptoclavidae Ponomarenko, 1961 | Extinct family | 1 | Species | Taxom |
| Cordulegastridae Calvert, 1893 | Biddie | 19 | Species | Taxom |
| Corduliidae Selys-Longch..., 1850 | Baskettails | 83 | Species | Taxom |
| Coreidae Leach, 1815 | Broad-headed bugs | 337 | Species | Taxom |
| Corethrellidae (Wood & Borkent, 1986) | Frog biting midge | 1 | Species | Taxom |
| Corioxenidae Kinzelbach, 1970 | | 10 | Species | Taxom |
| Corixidae Leach, 1815 | Lesser Water-Boatman | 191 | Species | Taxom |
| Corydalidae Burmeister, 1839 | Dobsonflies | 43 | Species | Taxom |
| Corydasialidae Wichard & al., 2005 | | 1 | Species | Taxom |
| Corydiidae de Saussure, 1864 | Sand cockroaches | 65 | Species | Taxom |
| Corylophidae LeConte, 1852 | Hooded beetles | 137 | Species | Taxom |
| Cosmopterigidae Heinemann & ..., 1876 | Cosmet Moths | 305 | Species | Taxom |
| Cosmopterygidae (Heinemann & ..., 1876) | Cosmet moths | 0 | Species | Taxom |
| Cossidae Leach, 1815 | Borers | 183 | Species | Taxom |
| Crabronidae Latreille, 1802 | Bee Wolves | 1606 | Species | Taxom |
| Crambidae Latreille, 1810 | Crambid Snout Moths | 2212 | Species | Taxom |
| Cretamyzidae Heie, 1992 | | 1 | Species | Taxom |
| Crosaphididae Kovalev, 1983 | | 1 | Species | Taxom |
| Cryptocercidae Handlirsch, 1925 | Brown-hooded cockroaches | 5 | Species | Taxom |
| Cryptochetidae Brues & Mela..., 1932 | Cryptochetid Flies | 1 | Species | Taxom |
| Cryptococcidae | | 3 | Species | Taxom |
| Cryptophagidae Kirby, 1937 | Mould beetles | 307 | Species | Taxom |
| Ctenophthalmidae Rothschild, 1915 | | 130 | Species | Taxom |
| Ctenuchidae (W. Kirby, 1837) | Ctenuchid moths | 2 | Species | Taxom |
| Cucujidae Latreille, 1802 | Flat bark beetles | 176 | Species | Taxom |
| Culicidae Meigen, 1818 | Mosquito | 518 | Species | Taxom |
| Cupedidae Laporte, 1836 | Cupedids | 17 | Species | Taxom |
| Curaliidae Schuh, Weira..., 2008 | | 1 | Species | Taxom |
| Curculionidae Latreille, 1802 | Ambrosia beetles | 9519 | Species | Taxom |
| Curtonotidae Duda, 1934 | Curtonotid flies | 7 | Species | Taxom |
| Cybocelphalidae | | 1 | Species | Taxom |
| Cydnidae Billberg, 1820 | Burrower bugs | 114 | Species | Taxom |
| Cylindrotomidae (Mulsant, 1842) | Cylindrotomid Crane Flies | 4 | Species | Taxom |
| Cymidae Baerensprung, 1860 | | 21 | Species | Taxom |
| Cynipidae Latreille, 1802 | Cynipid gall wasps | 952 | Species | Taxom |
| Cypselosomatidae Hennig, 1958 | Cypselosomatid flies | 3 | Species | Taxom |
| Dactylopiidae Signoret, 1875 | Cochineal insects | 13 | Species | Taxom |
| Dalceridae Dyar, 1898 | Dalcerid moths | 10 | Species | Taxom |
| Danaidae (Boisduval, 1833) | Milkweed Butterflies | 1 | Species | Taxom |
| Dascillidae Guérin-Ménev..., 1843 | Orchid beetles | 10 | Species | Taxom |
| Dasydemellidae | Shaggy Psocids | 3 | Species | Taxom |
| Delopteridae Sellards, 1909 | | 1 | Species | Taxom |
| Delphacidae Leach, 1815 | Delphacid planthoppers | 722 | Species | Taxom |
| Demopteridae Carpenter, 1950 | | 1 | Species | Taxom |
| Depressariidae Meyrick, 1883 | Flat-Bodied Moths | 4 | Species | Taxom |
| Derbidae Spinola, 1839 | Derbid planthoppers | 181 | Species | Taxom |
| Dericorythidae Jacobson & B..., 1902 | | 1 | Species | Taxom |
| Dermestidae Hope, 1840 | Carpet beetles | 322 | Species | Taxom |
| Dermopteridae | | 1 | Species | Taxom |
| Derodontidae LeConte, 1861 | Tooth-neck fungus beetles | 11 | Species | Taxom |
| Deuterophlebiidae Edwards, 1922 | Mountain midges | 6 | Species | Taxom |
| Diaphanopteridae Handlirsch, 1906 | | 1 | Species | Taxom |
| Diapheromeridae Rehn & Hebard, 1909 | Diapheromerid Stick Insects | 78 | Species | Taxom |
| Diapriidae Latreille, 1796 | Diapriid wasps | 429 | Species | Taxom |
| Diaspididae Maskell, 1878 | Armored scale insects | 660 | Species | Taxom |
| Diastatidae Hendel, 1917 | Bog flies | 10 | Species | Taxom |
| Dictyoneuridae Handlirsch, 1906 | | 0 | Species | Taxom |
| Dictyopharidae Spinola, 1839 | Dictyopharid Planthoppers | 114 | Species | Taxom |
| Dilaridae Newman, 1853 | Pleasing lacewing | 3 | Species | Taxom |
| Dinidoridae Stål, 1867 | Dinidorid bug | 1 | Species | Taxom |
| Dinoblattidae Durden, 1969 | | 3 | Species | Taxom |
| Dinopanorpidae Carpenter, 1972 | | 6 | Species | Taxom |
| Diopsidae Billberg, 1820 | Stalk-eyed flies | 3 | Species | Taxom |
| Dioptidae (J. Bechyné, 1950) | American False Tiger Moths | 1 | Species | Taxom |
| Diphyllostomatidae Holloway, 1972 | False stag beetles | 4 | Species | Taxom |
| Diplatyidae (Verhoeff, 1902) | | 3 | Species | Taxom |
| Diprionidae Rohwer, 1911 | Conifer sawflies | 61 | Species | Taxom |
| Dipseudopsidae Ulmer, 1904 | | 11 | Species | Taxom |
| Dipsocoridae Dohrn, 1859 | Dipsocorids | 3 | Species | Taxom |
| Dipteromantispidae Makarkin & al., 2013 | | 2 | Species | Taxom |
| Discolomatidae Horn, 1878 | | 5 | Species | Taxom |
| Ditaxineuridae Tillyard, 1926 | | 2 | Species | Taxom |
| Ditomyiidae Keilin, 1919 | | 18 | Species | Taxom |
| Dixidae Schiner, 1868 | Dixid Midges | 74 | Species | Taxom |
| Dolabellopsocidae Eertmoed, 1973 | | 1 | Species | Taxom |
| Dolichopodidae Latreille, 1809 | Long legged flies | 2218 | Species | Taxom |
| Douglasiidae Heinemann & ..., 1876 | Douglas Moths | 17 | Species | Taxom |
| Drepanidae Meyrick, 1895 | Drepanids | 49 | Species | Taxom |
| Drosophilidae Rondani, 1856 | Fruit flies | 896 | Species | Taxom |
| Dryinidae Haliday, 1840 | Dryinid wasps | 172 | Species | Taxom |
| Dryomyzidae Schiner, 1862 | Dryomyzid flies | 27 | Species | Taxom |
| Dryophthoridae (Schönherr, 1825) | Palm weevils | 5 | Species | Taxom |
| Dryopidae Billberg, 1820 | Long toed water beetle | 53 | Species | Taxom |
| Dytiscidae Leach, 1815 | Diving beetles | 1182 | Species | Taxom |
| Echinophthiriidae Enderlein, 1904 | | 6 | Species | Taxom |
| Ecnomidae Ulmer, 1903 | | 12 | Species | Taxom |
| Ectobiidae (Brunner von ..., 1865) | Wood cockroaches | 20 | Species | Taxom |
| Ectopsocidae | Outer Barklice | 36 | Species | Taxom |
| Elachistidae Bruand, 1851 | Elachistid moths | 686 | Species | Taxom |
| Elateridae Leach, 1815 | Click Beetle | 2035 | Species | Taxom |
| Elcanidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Electralbertidae Botosaneanu ..., 1983 | | 1 | Species | Taxom |
| Electrentomidae Enderlein, 1911 | | 3 | Species | Taxom |
| Electrococcidae Koteja, 2000 | | 3 | Species | Taxom |
| Elenchidae Perkins, 1905 | | 8 | Species | Taxom |
| Elipsocidae Pearman, 1936 | Damp Barklice | 25 | Species | Taxom |
| Ellinaphididae Kania & Wegi..., 2008 | | 2 | Species | Taxom |
| Elmidae Curtis, 1830 | Drive beetles | 249 | Species | Taxom |
| Elmoboriidae Carpenter, 1977 | | 1 | Species | Taxom |
| Elmoidae Tillyard, 1937 | | 1 | Species | Taxom |
| Elytroneuridae Carpenter, 1933 | | 1 | Species | Taxom |
| Embiidae Burmeister, 1839 | | 3 | Species | Taxom |
| Embolemidae Förster, 1856 | Embolemid wasps | 2 | Species | Taxom |
| Empheriidae Enderlein, 1906 | | 1 | Species | Taxom |
| Empididae Latreille, 1809 | Balloon flies | 851 | Species | Taxom |
| Encyrtidae Walker, 1837 | Encyrtid wasps | 808 | Species | Taxom |
| Enderleinellidae Ewing, 1929 | | 17 | Species | Taxom |
| Endomychidae Leach, 1815 | False Ladybirds | 136 | Species | Taxom |
| Eneopteridae (Saussure, 1893) | Bush cricket | 32 | Species | Taxom |
| Enicocephalidae Stål, 1860 | Gnat bug | 24 | Species | Taxom |
| Eoblattidae Handlirsch, 1906 | | 2 | Species | Taxom |
| Eomeropidae Cockerell, 1909 | | 2 | Species | Taxom |
| Eophlebomyiidae Cockerell, 1925 | | 1 | Species | Taxom |
| Eorpidae Archibald & al., 2013 | | 3 | Species | Taxom |
| Epallagidae Needham, 1903 | | 4 | Species | Taxom |
| Epermeniidae Spuler, 1910 | Epermeniid moths | 171 | Species | Taxom |
| Ephemerellidae (Klapálek, 1909) | Blue-Winged Olive Ephemerellidae | 127 | Species | Taxom |
| Ephemeridae Leach, 1817 | Burrowing mayflies | 31 | Species | Taxom |
| Ephydridae Zetterstedt, 1837 | Brine flies | 702 | Species | Taxom |
| Epideigmatidae Handlirsch, 1911 | | 1 | Species | Taxom |
| Epipsocidae | Elliptical bark louse | 4 | Species | Taxom |
| Epipygidae Hamilton, 2001 | | 1 | Species | Taxom |
| Epipyropidae Dyar, 1903 | Planthopper Parasite Moths | 3 | Species | Taxom |
| Episactidae Burr, 1899 | | 12 | Species | Taxom |
| Erebidae Leach, 1815 | Erebid Moths | 3445 | Species | Taxom |
| Eriococcidae Cockerell, 1899 | Eriococcid scales | 195 | Species | Taxom |
| Eriocottidae Spuler, 1898 | Old World Spiny Winged Moths | 1 | Species | Taxom |
| Eriocraniidae Rebel, 1901 | Eriocraniid moths | 17 | Species | Taxom |
| Erotylidae Latreille, 1802 | Pleasing Fungus Beetle | 171 | Species | Taxom |
| Eubleptidae Handlirsch, 1906 | | 2 | Species | Taxom |
| Eucaenidae Handlirsch, 1906 | | 5 | Species | Taxom |
| Eucharitidae Latreille, 1809 | Eucharitid wasp | 56 | Species | Taxom |
| Eucinetidae Lacordaire, 1857 | Plate-thigh beetle | 20 | Species | Taxom |
| Eucnemidae Eschscholtz, 1829 | Click Beetles | 118 | Species | Taxom |
| Eucoilidae (Thomson, 1862) | | 1 | Species | Taxom |
| Eugereonidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Eulichadidae Crowson, 1973 | Forest stream beetle | 2 | Species | Taxom |
| Eulophidae Westwood, 1829 | Eulophid wasps | 1439 | Species | Taxom |
| Eumastacidae Burr, 1898 | Matchstick grasshoppers | 24 | Species | Taxom |
| Eupelmidae Walker, 1833 | Eupelmid wasps | 180 | Species | Taxom |
| Eupterotidae Swinhoe, 1892 | Giant Lappet Moths | 2 | Species | Taxom |
| Eurybrachidae Stål, 1862 | | 2 | Species | Taxom |
| Eurytomidae Walker, 1832 | Eurytomid wasps | 453 | Species | Taxom |
| Euteliidae Grote, 1882 | Euteliid Moths | 51 | Species | Taxom |
| Euthyplociidae Lestage, 1921 | | 2 | Species | Taxom |
| Evaniidae Latreille, 1802 | Ensign wasp | 28 | Species | Taxom |
| Fanniidae Schnabl & Dz..., 1911 | Latrine flies | 138 | Species | Taxom |
| Fauriellidae Priesner, 1949 | | 1 | Species | Taxom |
| Fergusoninidae Hennig, 1958 | | 3 | Species | Taxom |
| Figitidae Thomson, 1862 | Figitid wasps | 276 | Species | Taxom |
| Flatidae Spinola, 1839 | Flatid planthoppers | 101 | Species | Taxom |
| Forficulidae Stephens, 1829 | Common Earwig | 32 | Species | Taxom |
| Formicidae Latreille, 1809 | Ant | 2795 | Species | Taxom |
| Fouqueidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Fulgoridae Latreille, 1807 | Fulgorid Planthopper | 75 | Species | Taxom |
| Galacticidae Minet, 1986 | Galacticid Moths | 2 | Species | Taxom |
| Galgulidae | | 1 | Species | Taxom |
| Gasteruptiidae Ashmead, 1900 | Carrot Wasps | 23 | Species | Taxom |
| Gelasopteridae Carpenter, 1976 | | 1 | Species | Taxom |
| Gelastocoridae Kirkaldy, 1897 | Toad bug | 13 | Species | Taxom |
| Gelechiidae Stainton, 1854 | Gelechiid moths | 1655 | Species | Taxom |
| Geocoridae Baerensprung, 1860 | Big-eyed Bugs | 45 | Species | Taxom |
| Geometridae Leach, 1815 | Cankerworm moths | 3819 | Species | Taxom |
| Georyssidae Laporte, 1819 | Minute mud-loving beetles | 2 | Species | Taxom |
| Geotrupidae Latreille, 1802 | Dor beetles | 166 | Species | Taxom |
| Gerapompidae Handlirsch, 1906 | | 4 | Species | Taxom |
| Geraridae Scudder, 1885 | | 11 | Species | Taxom |
| Gerridae Leach, 1815 | Jesus bugs | 97 | Species | Taxom |
| Glaphyridae MacLeay, 1819 | Bumble bee scarab beetle | 15 | Species | Taxom |
| Glaphyropteridae Pongracz, 1935 | | 1 | Species | Taxom |
| Glaresidae Kolbe, 1905 | Enigmatic scarab beetle | 33 | Species | Taxom |
| Glossinidae Theobald, 1903 | Tik-tik flies | 7 | Species | Taxom |
| Glossosomatidae Wallengren, 1891 | Little Black Caddisflies | 169 | Species | Taxom |
| Glyphipterigidae Stainton, 1854 | Glyphipterigid moths | 64 | Species | Taxom |
| Goeridae Ulmer, 1903 | | 18 | Species | Taxom |
| Gomphaeschnidae Tillyard & F..., 1940 | | 1 | Species | Taxom |
| Gomphidae Rambur, 1842 | Club-tailed dragonflies | 231 | Species | Taxom |
| Gracillariidae Stainton, 1854 | Blotch leaf miner moths | 565 | Species | Taxom |
| Grassyaphididae Heie, 2000 | | 1 | Species | Taxom |
| Grimaldiellidae Koteja, 2000 | | 2 | Species | Taxom |
| Gripopterygidae Enderlein, 1909 | | 2 | Species | Taxom |
| Gryllacrididae Blanchard, 1845 | Camel Crickets | 13 | Species | Taxom |
| Gryllidae Bolivar, 1878 | Crickets | 85 | Species | Taxom |
| Grylloblattidae E. M. Walker, 1914 | Grylloblattids | 16 | Species | Taxom |
| Gryllotalpidae Saussure, 1870 | Mole cricket | 26 | Species | Taxom |
| Gyrinidae Latreille, 1802 | Whirligig beetle | 108 | Species | Taxom |
| Gyroblattidae Durden, 1969 | | 6 | Species | Taxom |
| Gyropidae Kellogg, 1896 | | 7 | Species | Taxom |
| Hadentomidae Handlirsch, 1906 | | 2 | Species | Taxom |
| Haematopinidae Enderlein, 1904 | Ungulate lice | 13 | Species | Taxom |
| Haglidae Handlirsch, 1906 | Hump-winged cricket | 5 | Species | Taxom |
| Halictidae Thomson, 1869 | Flower bees | 1303 | Species | Taxom |
| Halictophagidae Perkins, 1905 | | 28 | Species | Taxom |
| Halimococcidae Brown & McKe..., 1962 | Halimococcids | 9 | Species | Taxom |
| Haliplidae Aubé, 1836 | Crawling Water Beetle | 102 | Species | Taxom |
| Hanidae Kukalova-Peck, 1975 | | 1 | Species | Taxom |
| Hapalopteridae Handlirsch, 1906 | | 7 | Species | Taxom |
| Hebridae Amyot and Se..., 1843 | Velvet water bug | 25 | Species | Taxom |
| Hedylidae Guenée, 1857 | American Butterfly Moths | 9 | Species | Taxom |
| Helcomyzidae Malloch, 1933 | Helcomyzid flies | 2 | Species | Taxom |
| Heleomyzidae (Westwood, 1840) | Heleomyzid flies | 227 | Species | Taxom |
| Heliconiidae (Swainson, 1822) | Heliconians | 0 | Species | Taxom |
| Helicopsychidae Ulmer, 1912 | Snail Case caddisflies | 33 | Species | Taxom |
| Heliodinidae Heinemann & ..., 1876 | Heliodinid moths | 49 | Species | Taxom |
| Heliozelidae Heinemann & ..., 1876 | Leaf miners | 52 | Species | Taxom |
| Helophoridae (Leach, 1815) | Water scavenger beetles | 1 | Species | Taxom |
| Heloridae Förster, 1856 | Helorid wasps | 3 | Species | Taxom |
| Helosciomyzidae Griffiths, 1972 | | 1 | Species | Taxom |
| Helotidae Reitter, 1876 | | 3 | Species | Taxom |
| Hemerobiidae Latreille, 1802 | Brown Lacewing | 143 | Species | Taxom |
| Hemimylacridae Waterlot, 1934 | | 10 | Species | Taxom |
| Hemiphlebiidae Fraser, 1960 | Ancient greenling | 1 | Species | Taxom |
| Hemipsocidae Pearman, 1936 | Leaf Litter Barklice | 4 | Species | Taxom |
| Henrotayiidae Fleck, Bechl..., 2003 | | 1 | Species | Taxom |
| Hepialidae Stephens, 1829 | Ghost Moths | 73 | Species | Taxom |
| Heptageniidae Needham, 1901 | Flat-Bodied Up-Wings Heptageniidae | 228 | Species | Taxom |
| Herdinidae Carpenter & ..., 1972 | | 1 | Species | Taxom |
| Hesperiidae Latreille, 1809 | Indet. Skipper | 1996 | Species | Taxom |
| Hesperinidae Hendel, 1928 | | 1 | Species | Taxom |
| Heteroceridae MacLeay, 1825 | Mud beetles | 94 | Species | Taxom |
| Heterocheilidae Mcalpine, 1991 | Half-bridge flies | 3 | Species | Taxom |
| Heterogastridae Stål, 1872 | | 3 | Species | Taxom |
| Heterogynidae Rambur, 1866 | Mediterranean Burnet Moths | 0 | Species | Taxom |
| Heteromyzidae Fallen, 1820 | Heleomyzid flies | 2 | Species | Taxom |
| Heteronemiidae Rehn, J. A. G., 1904 | | 10 | Species | Taxom |
| Heteroptilidae Carpenter, 1977 | | 1 | Species | Taxom |
| Heterothripidae Bagnall, 1912 | | 29 | Species | Taxom |
| Hilarimorphidae Hendel, 1936 | Hilarimorphid flies | 31 | Species | Taxom |
| Hippoboscidae Samouelle, 1819 | Keds | 120 | Species | Taxom |
| Histeridae Gyllenhal, 1808 | Clown beetle | 1167 | Species | Taxom |
| Homoiopteridae Handlirsch, 1906 | | 9 | Species | Taxom |
| Homotomidae Heslop-Harrison, 1958 | | 5 | Species | Taxom |
| Hoplopleuridae Ewing, 1929 | | 22 | Species | Taxom |
| Hyblaeidae Hampson, 1903 | Teak Moths | 2 | Species | Taxom |
| Hybosoridae Erichson, 1847 | Pill scarab beetles | 43 | Species | Taxom |
| Hybotidae Meigen, 1820 | Dance flies | 482 | Species | Taxom |
| Hydraenidae Mulsant, 1844 | Cascade Beetles | 176 | Species | Taxom |
| Hydrobiosidae Ulmer, 1905 | | 131 | Species | Taxom |
| Hydrometridae Billberg, 1820 | Marsh treader | 20 | Species | Taxom |
| Hydrophilidae Latreille, 1802 | Silver Water Beetles | 686 | Species | Taxom |
| Hydropsychidae Curtis, 1835 | Net Spinning caddisflies | 242 | Species | Taxom |
| Hydroptilidae Stephens, 1836 | Micro caddisflies | 649 | Species | Taxom |
| Hydroscaphidae LeConte, 1874 | Skiff beetle | 2 | Species | Taxom |
| Hylicellidae Evans, 1956 | | 1 | Species | Taxom |
| Hymenopodidae Giglio-Tos, 1919 | Flower mimic mantises | 7 | Species | Taxom |
| Hystrichopsyllidae Tiraboschi, 1904 | Insectivore fleas | 65 | Species | Taxom |
| Ibaliidae Thomson, 1862 | Ibaliid wasps | 11 | Species | Taxom |
| Ichneumonidae Latreille, 1802 | Ichneumon flies | 6047 | Species | Taxom |
| Ideliidae (Zalessky, 1929) | | 1 | Species | Taxom |
| Idelinellidae Storozhenko, 1997 | | 1 | Species | Taxom |
| Idiomylacridae Handlirsch, 1906 | | 1 | Species | Taxom |
| Idiostolidae Scudder, 1962 | | 1 | Species | Taxom |
| Immidae Heppner, 1977 | Imma Moths | 1 | Species | Taxom |
| Incurvariidae Spuler, 1898 | Fairy moths | 26 | Species | Taxom |
| Inocelliidae Navas, 1913 | Inocelliid snakeflies | 6 | Species | Taxom |
| Ironomyiidae McAlpine & M..., 1966 | Ironic flies | 1 | Species | Taxom |
| Ischnoneuridae Handlirsch, 1906 | | 1 | Species | Taxom |
| Ischnopsyllidae Wahlgren, 1907 | Bat fleas | 19 | Species | Taxom |
| Isostictidae Fraser, 1955 | Narrow-wings | 1 | Species | Taxom |
| Issidae Spinola, 1839 | Issid planthoppers | 90 | Species | Taxom |
| Ithonidae Newman, 1838 | Ithonid lacewings | 7 | Species | Taxom |
| Ithyceridae (Schönherr, 1826) | New York weevil | 2 | Species | Taxom |
| Jacobsoniidae Heller, 1926 | Jacobson's beetles | 2 | Species | Taxom |
| Jantarimantidae Vrsansky, 2002 | | 1 | Species | Taxom |
| Jascopidae Hamilton, 1971 | | 1 | Species | Taxom |
| Jersicoccidae Koteja, 2000 | | 3 | Species | Taxom |
| Kalotermitidae Froggatt, 1897 | Dampwood termites | 54 | Species | Taxom |
| Kateretidae Kirkby, 1837 | Pollen Beetles | 4 | Species | Taxom |
| Kennedyidae Tillyard, 1925 | | 10 | Species | Taxom |
| Kermesidae Signoret, 1875 | Gall-like Scale Insects | 48 | Species | Taxom |
| Keroplatidae Rondani, 1856 | Fungus gnats | 172 | Species | Taxom |
| Kerriidae Lindinger, 1937 | Lac Insects | 8 | Species | Taxom |
| Kinnaridae Muir, 1925 | Kinnarid Planthoppers | 13 | Species | Taxom |
| Kohlwaldiidae Guthörl, 1962 | | 1 | Species | Taxom |
| Krausichnidae Genise, 2004 | | 0 | Species | Taxom |
| Kukaspididae Koteja & Poinar, 2001 | | 1 | Species | Taxom |
| Kuwaniidae MacGillvray, 1921 | | 3 | Species | Taxom |
| Labiduridae Verhoeff, 1902 | Long-horned earwig | 11 | Species | Taxom |
| Labiidae (Burr, 1909) | Little earwig | 22 | Species | Taxom |
| Labiococcidae Koteja, 2000 | | 2 | Species | Taxom |
| Labradorocoleidae Ponomarenko, 1969 | | 1 | Species | Taxom |
| Lachesillidae Pearman, 1936 | Fateful Barklice | 169 | Species | Taxom |
| Lacturidae Heppner, 1995 | Australian burnet moths | 9 | Species | Taxom |
| Laemobothriidae Mjöberg, 1910 | | 12 | Species | Taxom |
| Laemophloeidae (Ganglbauer, 1899) | Lined flat bark beetles | 3 | Species | Taxom |
| Lalacidae Hamilton, 1990 | | 1 | Species | Taxom |
| Lampyridae Latreille, 1817 | Fireflies | 368 | Species | Taxom |
| Largidae Amyot and Se..., 1843 | Bordered plant bugs | 39 | Species | Taxom |
| Lasiocampidae Harris, 1841 | Eggar Moths | 172 | Species | Taxom |
| Latridiidae Erichson, 1842 | Minute brown scavenger beetle | 259 | Species | Taxom |
| Lauxaniidae Macquart, 1835 | Beach flies | 286 | Species | Taxom |
| Lecanodiaspididae Borchsenius, 1965 | False pit scales | 14 | Species | Taxom |
| Lecithoceridae Le Marchand, 1947 | Long-horned moths | 7 | Species | Taxom |
| Leiodidae Fleming, 1821 | Round fungus beetles | 738 | Species | Taxom |
| Lemmatophoridae Sellards, 1909 | | 11 | Species | Taxom |
| Lemoniidae Hampson, 1918 | Autumn Silkworm Moths | 1 | Species | Taxom |
| Lepiceridae Hinton, 1936 | | 2 | Species | Taxom |
| Lepidopsocidae Lienhard & S..., 2002 | Scaly-winged bark louse | 33 | Species | Taxom |
| Lepidostomatidae Ulmer, 1903 | Bizarre Caddisflies | 126 | Species | Taxom |
| Leptaphelocheiridae Polhemus, 2000 | | 1 | Species | Taxom |
| Leptoceridae Leach, 1815 | Long Horned caddisflies | 283 | Species | Taxom |
| Leptohyphidae Landa & Soldán, 1985 | Little Stout Crawler Mayflies | 59 | Species | Taxom |
| Leptophlebiidae Banks, 1900 | Leptophlebiids | 122 | Species | Taxom |
| Leptopodidae Amyot and Se..., 1843 | Spiny shore bugs | 4 | Species | Taxom |
| Leptopsyllidae Rothschild &..., 1915 | Bird fleas | 33 | Species | Taxom |
| Lestidae Calvert, 1901 | Spread-winged damselflies | 36 | Species | Taxom |
| Leucospidae Fabricius, 1775 | Leucospid wasps | 20 | Species | Taxom |
| Leuctridae Klapálek, 1905 | Needle Or Willow Stoneflies | 94 | Species | Taxom |
| Liadopsyllidae Martynov, 1927 | | 1 | Species | Taxom |
| Libellulidae Rambur, 1842 | Chasers | 253 | Species | Taxom |
| Limacodidae Duponchel, 1845 | Cup moths | 149 | Species | Taxom |
| Limnephilidae Kolenati, 1848 | Northern caddisflies | 429 | Species | Taxom |
| Limnichidae Erichson, 1846 | Minute marsh loving beetle | 75 | Species | Taxom |
| Limoniidae (Speiser, 1909) | Craneflies | 220 | Species | Taxom |
| Linognathidae Webb, 1946 | | 16 | Species | Taxom |
| Liomopteridae Sellards, 1909 | | 8 | Species | Taxom |
| Liopteridae Ashmead, 1895 | Liopterid wasps | 14 | Species | Taxom |
| Liposcelididae Enderlein, 1911 | Booklice | 54 | Species | Taxom |
| Lithomanteidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Lithoneuridae Sroka & al., 2014 | | 5 | Species | Taxom |
| Lithopanorpidae Carpenter, 1930 | | 1 | Species | Taxom |
| Liturgusidae Giglio-Tos, 1919 | | 8 | Species | Taxom |
| Liviidae Low, 1879 | | 58 | Species | Taxom |
| Locustopsidae Handlirsch, 1906 | | 5 | Species | Taxom |
| Lonchaeidae Loew, 1861 | Lance Flies | 176 | Species | Taxom |
| Lonchopteridae Curtis, 1839 | Pointed-wing flies | 11 | Species | Taxom |
| Lophioneuridae Tillyard, 1921 | | 4 | Species | Taxom |
| Lophocoronidae Common, 1973 | Australian Archaic Sun Moths | 1 | Species | Taxom |
| Lucanidae Latreille, 1804 | Stag Beetle | 115 | Species | Taxom |
| Luiseiidae Nel & al., 2012 | | 1 | Species | Taxom |
| Lutrochidae Kasap & Crowson, 1975 | Robust marsh loving beetle | 4 | Species | Taxom |
| Lycaenidae Leach, 1815 | And blues | 1240 | Species | Taxom |
| Lycanidae (Leach, 1815) | | 1 | Species | Taxom |
| Lycidae Laporte, 1836 | Lycid beetles | 195 | Species | Taxom |
| Lycocercidae Handlirsch, 1906 | | 4 | Species | Taxom |
| Lygaeidae Schilling, 1829 | Chinch bugs | 362 | Species | Taxom |
| Lygistorrhinidae Hendel, 1936 | Long beaked fungus gnat | 2 | Species | Taxom |
| Lygobiidae Mitchell, 1908 | | 1 | Species | Taxom |
| Lymexylidae Fleming, 1821 | Ship-timber beetle | 8 | Species | Taxom |
| Lyonetiidae Stainton, 1854 | Lyonet Moths | 181 | Species | Taxom |
| Macroveliidae McKinstry, 1942 | Macroveliid shore bugs | 3 | Species | Taxom |
| Maimetshidae (Rasnitsyn, 1975) | | 3 | Species | Taxom |
| Malcidae Stål, 1865 | | 1 | Species | Taxom |
| Mantidae Burmeister, 1838 | Mantids | 89 | Species | Taxom |
| Mantispidae Leach, 1815 | Mantid lacewings | 49 | Species | Taxom |
| Mantoididae Giglio-Tos, 1927 | | 3 | Species | Taxom |
| Marchalinidae Morrison, 1927 | | 1 | Species | Taxom |
| Margarodidae Newstead, 1901 | Cottony cushion scales | 16 | Species | Taxom |
| Martynoviidae Tillyard, 1932 | | 8 | Species | Taxom |
| Mastotermitidae Desneux, 1904 | | 2 | Species | Taxom |
| Matsucoccidae Morrison, 1927 | Pine bark scales | 23 | Species | Taxom |
| Mauroniscidae Majer, 1995 | Mauroniscid Beetles | 8 | Species | Taxom |
| Meenoplidae Fieber, 1872 | | 1 | Species | Taxom |
| Megachilidae Schenk, 1860 | And Resin Bees | 1332 | Species | Taxom |
| Megakhosaridae Sharov, 1961 | | 2 | Species | Taxom |
| Megalopodidae Latreille, 1802 | Megalopodid Leaf Beetles | 19 | Species | Taxom |
| Megalopygidae Herrich-Schä..., 1855 | Crinkled Flannel Moths | 49 | Species | Taxom |
| Megalyridae Schletterer, 1889 | Megalyrid wasps | 1 | Species | Taxom |
| Megamerinidae Hendel, 1913 | Megamerinid flies | 1 | Species | Taxom |
| Meganeuridae Handlirsch, 1906 | | 17 | Species | Taxom |
| Megapodagrionidae Tillyard, 1917 | Flatwing | 21 | Species | Taxom |
| Megarididae McAtee & Mal..., 1928 | | 1 | Species | Taxom |
| Megaspilidae Ashmead, 1893 | Megaspilid wasps | 96 | Species | Taxom |
| Megelytridae Carpenter, 1933 | | 1 | Species | Taxom |
| Melandryidae Leach, 1815 | False Darkling Beetle | 103 | Species | Taxom |
| Melanthripidae Bagnall, 1913 | | 14 | Species | Taxom |
| Melinophlebiidae Durden, 1969 | | 2 | Species | Taxom |
| Melittidae Schenk, 1860 | Melittid bees | 49 | Species | Taxom |
| Meloidae Gyllenhal, 1810 | Blister Beetle | 710 | Species | Taxom |
| Melolonthidae (Leach, 1817) | Chafers | 2 | Species | Taxom |
| Melyridae Leach, 1815 | Malachite Beetles | 642 | Species | Taxom |
| Membracidae Germar, 1821 | Horned Treehoppers | 641 | Species | Taxom |
| Menoponidae Mjöberg, 1910 | Bird lice | 345 | Species | Taxom |
| Meropeidae Espen-Petersen, 1921 | Earwig-flies | 1 | Species | Taxom |
| Merothripidae Hood, 1914 | Large-legged thrips | 7 | Species | Taxom |
| Mesoblattinidae Handlirsch, 1906 | | 3 | Species | Taxom |
| Mesokristenseniidae Huang, Nel &..., 2010 | | 1 | Species | Taxom |
| Mesopsocidae Enderlein, 1903 | Middle Barklice | 4 | Species | Taxom |
| Mesopsychidae Tillyard, 1917 | | 1 | Species | Taxom |
| Mesoraphidiidae Martynov, 1925 | | 2 | Species | Taxom |
| Mesoveliidae Douglas and ..., 1867 | Pond treaders | 10 | Species | Taxom |
| Mesozoicaphididae Heie, 1992 | | 6 | Species | Taxom |
| Metropatoridae Handlirsch, 1906 | | 1 | Species | Taxom |
| Micromalthidae Barber, 1913 | Micromalthid beetles | 1 | Species | Taxom |
| Micronectidae Jaczewski, 1924 | Pygmy water boatmen | 5 | Species | Taxom |
| Micropezidae Illiger, 1798 | Stilt Flies | 93 | Species | Taxom |
| Microphysidae Dohrn, 1859 | Microphysid bugs | 11 | Species | Taxom |
| Micropterigidae Herrich-Schä..., 1855 | Mandibulate Archaic Moths | 6 | Species | Taxom |
| Milichiidae Schiner, 1862 | Filth flies | 81 | Species | Taxom |
| Mimallonidae Burmeister, 1878 | Mimallonid Moths | 27 | Species | Taxom |
| Miridae Hahn, 1831 | Capsid bugs | 3570 | Species | Taxom |
| Mirinidae (Kozlov, 1985) | | 0 | Species | Taxom |
| Mischopteridae Handlirsch, 1906 | | 1 | Species | Taxom |
| Misthodotidae Tillyard, 1932 | | 7 | Species | Taxom |
| Mogoplistidae Saussure, 1877 | Scaly cricket | 39 | Species | Taxom |
| Molannidae Wallengren, 1891 | Hood Casemaker Caddisflies | 3 | Species | Taxom |
| Monomachidae Ashmead, 1902 | Monomachid wasps | 4 | Species | Taxom |
| Monophlebidae Signoret, 1875 | Giant scale | 30 | Species | Taxom |
| Monotomidae Laporte, 1840 | Minute Clubbed Beetles | 104 | Species | Taxom |
| Morabidae Rehn, 1948 | | 1 | Species | Taxom |
| Mordellidae Latreille, 1802 | Pintail beetles | 440 | Species | Taxom |
| Musapsocidae Mockford, 1967 | | 3 | Species | Taxom |
| Muscidae Latreille, 1802 | Face flies | 1136 | Species | Taxom |
| Mutillidae André, 1907 | Cow ant | 614 | Species | Taxom |
| Mycetophagidae Leach, 1815 | Hairy fungus beetle | 55 | Species | Taxom |
| Mycetophilidae Newman, 1834 | Fungus Gnat | 1683 | Species | Taxom |
| Mycteridae Blanchard, 1845 | Mycterid beetles | 23 | Species | Taxom |
| Mydaidae (Osten Sacken, 1874) | Mydas flies | 2 | Species | Taxom |
| Mydidae Bezzi, 1903 | Mydas flies | 137 | Species | Taxom |
| Myerslopiidae Evans, 1957 | | 1 | Species | Taxom |
| Mylacridae Scudder, 1886 | | 47 | Species | Taxom |
| Mymaridae Haliday, 1833 | Fairflies | 304 | Species | Taxom |
| Mymarommatidae Debauche, 1948 | False fairy wasp | 28 | Species | Taxom |
| Myopsocidae Enderlein, 1907 | Mouse like barklouse | 12 | Species | Taxom |
| Myrmecolacidae Saunders, 1872 | | 9 | Species | Taxom |
| Myrmecophilidae Saussure, 1874 | Ant cricket | 10 | Species | Taxom |
| Myrmeleontidae Latreille, 1802 | Ant lions | 218 | Species | Taxom |
| Mythicomyiidae Melander, 1902 | Micro Bee Flies | 2 | Species | Taxom |
| Nabidae Costa, 1852 | Damsel bugs | 90 | Species | Taxom |
| Namurodiaphidae Kukalová-Pec..., 1990 | | 1 | Species | Taxom |
| Narkemidae Handlirsch, 1911 | | 2 | Species | Taxom |
| Naucoridae Leach, 1815 | Creeping water bug | 59 | Species | Taxom |
| Necymylacridae Durden, 1969 | | 5 | Species | Taxom |
| Nemestrinidae Macquart, 1834 | Tangle-veined flies | 22 | Species | Taxom |
| Nemonychidae Bedel, 1882 | Nemonychid weevils | 28 | Species | Taxom |
| Nemopteridae Rambur, 1842 | Spoonwings | 4 | Species | Taxom |
| Nemouridae Newman, 1853 | Brown stoneflies | 128 | Species | Taxom |
| Neoephemeridae Traver, 1935 | Large square-gilled mayflies | 8 | Species | Taxom |
| Neorthroblattinidae Handlirsch, 1906 | | 3 | Species | Taxom |
| Nepidae Latreille, 1802 | Back-swimmer Water-boatmen | 28 | Species | Taxom |
| Nepticulidae Stainton, 1854 | Leaf miners | 262 | Species | Taxom |
| Neriidae Hendel, 1916 | Banana stalk flies | 10 | Species | Taxom |
| Nesameletidae (Kluge, Stude..., 1995) | | 1 | Species | Taxom |
| Neurostigmatidae | | 1 | Species | Taxom |
| Ninidae Barber, 1956 | | 1 | Species | Taxom |
| Nitidulidae Latreille, 1802 | Nitidules | 417 | Species | Taxom |
| Nocticolidae Bolivar, 1892 | Australian cockroaches | 12 | Species | Taxom |
| Nocticolinae | | 1 | Species | Taxom |
| Noctuidae Latreille, 1809 | Armyworms | 6157 | Species | Taxom |
| Nogodinidae Melichar, 1898 | | 82 | Species | Taxom |
| Nolidae Hampson, 1894 | Hatted Caterpillars | 151 | Species | Taxom |
| Nosodendridae Erichson, 1846 | Nosodendrid beetles | 10 | Species | Taxom |
| Noteridae C. G. Thomson, 1860 | Burrowing water beetle | 42 | Species | Taxom |
| Notodontidae Stephens, 1829 | Bag Shelter Moths | 578 | Species | Taxom |
| Notonectidae Latreille, 1802 | Back Swimmers | 71 | Species | Taxom |
| Nugonioneuridae Carpenter, 1976 | | 1 | Species | Taxom |
| Nycteribiidae Samouelle, 1819 | Bat Flies | 3 | Species | Taxom |
| Nymphalidae Rafinesque, 1815 | Admirals | 1841 | Species | Taxom |
| Nymphomyiidae Tokunaga, 1932 | Nymphomyiid crane flies | 2 | Species | Taxom |
| Ochodaeidae Mulsant & Rey, 1870 | Sand-loving scarab beetle | 55 | Species | Taxom |
| Odiniidae Hendel, 1920 | Odiniid flies | 16 | Species | Taxom |
| Odontoceridae Wallengren, 1891 | Mortarjoint Casemaker Caddisflies | 23 | Species | Taxom |
| Oecanthidae (Blanchard, 1845) | Tree cricket | 34 | Species | Taxom |
| Oeconesidae Tillyard, 1921 | | 2 | Species | Taxom |
| Oecophoridae Bruand, 1851 | Concealer Moths | 156 | Species | Taxom |
| Oedemeridae Latreille, 1810 | False Blister Beetle | 130 | Species | Taxom |
| Oedischiidae Handlirsch, 1906 | | 3 | Species | Taxom |
| Oestridae Leach, 1815 | Bot flies | 84 | Species | Taxom |
| Oligoneuriidae Ulmer, 1914 | Brushleg Mayflies | 35 | Species | Taxom |
| Oligotomidae Enderlein, 1909 | | 6 | Species | Taxom |
| Omaniidae Cobben, 1970 | Intertidal dwarf bug | 1 | Species | Taxom |
| Omethidae LeConte, 1861 | False fireflies | 12 | Species | Taxom |
| Ommatidae Sharp & Muir, 1912 | | 1 | Species | Taxom |
| Ommexechidae Bolivar, 1884 | | 1 | Species | Taxom |
| Opomyzidae (Fallen, 1820) | Opomyzid flies | 16 | Species | Taxom |
| Opostegidae Meyrick, 1893 | Opostegid moths | 30 | Species | Taxom |
| Oreoleptidae Zloty, Sincl..., 2005 | | 1 | Species | Taxom |
| Ormyridae Förster, 1856 | Armyrids | 22 | Species | Taxom |
| Orsodacnidae Thomson, 1859 | Orsodacnid Leaf Beetles | 27 | Species | Taxom |
| Ortheziidae Green, 1896 | Ensign coccids | 72 | Species | Taxom |
| Orthomylacridae see Durden, 1969 | | 44 | Species | Taxom |
| Orussidae Newman, 1834 | Orussid wasps | 13 | Species | Taxom |
| Osmylidae Leach, 1815 | Giant lacewings | 3 | Species | Taxom |
| Osmylopsychopidae Martynova, 1949 | | 0 | Species | Taxom |
| Otitidae (Macquart, 1835) | Picture-winged flies | 208 | Species | Taxom |
| Oviparosiphidae Shaposhnikov, 1979 | | 1 | Species | Taxom |
| Oxycarenidae Stål, 1862 | | 24 | Species | Taxom |
| Oxycorynidae (Schoenherr, 1840) | Oxycorynid weevils | 1 | Species | Taxom |
| Oxypeltidae Lacordaire, 1869 | | 2 | Species | Taxom |
| Pachygronthidae Stål, 1865 | | 11 | Species | Taxom |
| Pachyneuridae Schiner, 1864 | Dark-winged fungus gnats | 1 | Species | Taxom |
| Pachytroctidae Enderlein, 1911 | Thick Barklice | 14 | Species | Taxom |
| Palaeoaphididae Richards, 1966 | | 3 | Species | Taxom |
| Palaeoblattidae Cockerell, 1927 | | 1 | Species | Taxom |
| Palaeoleontidae Martins-Neto, 1992 | Ant lion | 2 | Species | Taxom |
| Palaeomanteidae Handlirsch, 1906 | | 11 | Species | Taxom |
| Palaeontinidae Handlirsch, 1906 | Giant cicadas | 1 | Species | Taxom |
| Palaephatidae Davis, 1986 | Gondwanaland Moths | 0 | Species | Taxom |
| Paleoblattidae Scudder, 1879 | | 18 | Species | Taxom |
| Paleuthygrammatidae Carpenter, 1943 | | 2 | Species | Taxom |
| Palingeniidae Albarda, 1888 | Riverbed Burrower Mayflies | 1 | Species | Taxom |
| Pallopteridae Loew, 1862 | Flutter flies | 23 | Species | Taxom |
| Pamphagidae Burmeister, 1840 | Toad grasshopper | 3 | Species | Taxom |
| Pamphiliidae Cameron, 1890 | Leaf-rolling sawflies | 105 | Species | Taxom |
| Panorpidae Linnaeus, 1758 | Common scorpionflies | 85 | Species | Taxom |
| Panorpodidae Byers, 1965 | Short-faced scorpionflies | 6 | Species | Taxom |
| Pantophthalmidae Williston, 1906 | Timber flies | 5 | Species | Taxom |
| Papilionidae Latreille, 1802 | Apollos | 365 | Species | Taxom |
| Parabrodiidae Carpenter, 1934 | | 1 | Species | Taxom |
| Paragryllidae (Desutter-Gra..., 1987) | | 9 | Species | Taxom |
| Paralogidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Paraxymyiidae Rohdendorf, 1946 | Paxylommatid wasps | 4 | Species | Taxom |
| Parelmoidae Rohdendorf, 1962 | | 4 | Species | Taxom |
| Parmapteridae Aristov & Ra..., 2015 | | 1 | Species | Taxom |
| Passalidae Leach, 1815 | Bess beetle | 157 | Species | Taxom |
| Pecaroecidae Kéler, 1963 | | 1 | Species | Taxom |
| Pediciidae Osten Sacken, 1860 | Hairy-Eyed Crane Flies | 20 | Species | Taxom |
| Pedicinidae Enderlein, 1904 | | 4 | Species | Taxom |
| Pediculidae Leach, 1817 | | 7 | Species | Taxom |
| Pelecinidae Haliday, 1839 | Ancestral And Modern Pelecinid Wasps | 4 | Species | Taxom |
| Pelecorhynchidae Philip, 1941 | Pelecorhynchid flies | 10 | Species | Taxom |
| Peltoperlidae Claassen, 1931 | Roach stoneflies | 32 | Species | Taxom |
| Pentatomidae Leach, 1815 | Lesser shield bugs | 465 | Species | Taxom |
| Perforissidae Shcherbakov, 2007 | | 1 | Species | Taxom |
| Pergidae Rohwer, 1911 | Pergid flies | 37 | Species | Taxom |
| Perilampidae Latreille, 1809 | Perilampid waps | 56 | Species | Taxom |
| Perilestidae Tillyard & F..., 1938 | Shortwings | 4 | Species | Taxom |
| Peripsocidae Roesler, 1944 | Stout Barklice | 38 | Species | Taxom |
| Periscelididae Oldenberg, 1914 | Periscelidid Flies | 22 | Species | Taxom |
| Perlidae (Latreille, 1802) | Common stoneflies | 230 | Species | Taxom |
| Perlodidae Klapálek, 1912 | Perlodid stoneflies | 220 | Species | Taxom |
| Permelcanidae Sharov, 1962 | | 2 | Species | Taxom |
| Permelytridae Tillyard, 1931 | | 9 | Species | Taxom |
| Permithonidae Tillyard, 1922 | | 1 | Species | Taxom |
| Permoberothidae Tillyard, 1932 | | 1 | Species | Taxom |
| Permobiellidae Tillyard, 1937 | | 2 | Species | Taxom |
| Permochoristidae Tillyard, 1918 | | 4 | Species | Taxom |
| Permopanorpidae Tillyard, 1926 | | 3 | Species | Taxom |
| Permopsocidae Tillyard, 1926 | | 5 | Species | Taxom |
| Permoraphidiidae Tillyard, 1932 | | 2 | Species | Taxom |
| Permothemidae Martynov, 1935 | | 1 | Species | Taxom |
| Personidae Gray, 1854 | | 12 | Species | Taxom |
| Petaluridae Needham, 1903 | Grayback dragonfly | 2 | Species | Taxom |
| Petrablattinidae Durden, 1969 | | 10 | Species | Taxom |
| Phalacridae Leach, 1815 | Shining flower beetles | 145 | Species | Taxom |
| Phalangopsidae (Chopard, 1949) | Spider cricket | 59 | Species | Taxom |
| Phasmatidae Roberts, 1944 | Walking sticks | 14 | Species | Taxom |
| Phasmomimidae Sharov, 1968 | | 4 | Species | Taxom |
| Phengodidae LeConte, 1861 | Glow-worms | 98 | Species | Taxom |
| Phenopteridae Carpenter, 1950 | | 1 | Species | Taxom |
| Philopotamidae Stephens, 1829 | Finger Net caddisflies | 125 | Species | Taxom |
| Philopteridae Burmeister, 1830 | | 753 | Species | Taxom |
| Philotarsidae Pearman, 1936 | Loving Barklice | 28 | Species | Taxom |
| Phlaeothripidae Uzel, 1895 | Thrips | 651 | Species | Taxom |
| Phoberoblattidae Durden, 1969 | | 9 | Species | Taxom |
| Phoenicococcidae Stickney, 1934 | Palm scales | 1 | Species | Taxom |
| Phoridae Curtis, 1833 | Coffin Flies | 748 | Species | Taxom |
| Phryganeidae (Leach, 1815) | Giant casemaker | 40 | Species | Taxom |
| Phylliidae Redtenbacher, 1906 | Leaf insects | 0 | Species | Taxom |
| Phylloxeridae Herrich-Scha..., 1854 | Phylloxeran Aphids | 70 | Species | Taxom |
| Phyloblattidae Schneider, 1983 | | 1 | Species | Taxom |
| Pieridae Duponchel, 1835 | And Sulphurs | 415 | Species | Taxom |
| Piesmatidae Amyot & Audi..., 1843 | Ash grey leaf bug | 19 | Species | Taxom |
| Piophilidae Macquart, 1835 | Cheese flies | 81 | Species | Taxom |
| Pipunculidae Walker, 1834 | Big headed flies | 317 | Species | Taxom |
| Pityococcidae Mckenzie, 1942 | | 6 | Species | Taxom |
| Plataspidae (Dallas, 1851) | | 3 | Species | Taxom |
| Plataspididae (Dallas, 1851) | | 0 | Species | Taxom |
| Platycnemididae Tillyard, 1917 | White-legged damselflies | 2 | Species | Taxom |
| Platygastridae Haliday, 1833 | Platygastrid wasps | 334 | Species | Taxom |
| Platypezidae Fallen, 1815 | Flat footed flies | 115 | Species | Taxom |
| Platystictidae Laidlaw, 1924 | Forest Damselflies | 13 | Species | Taxom |
| Platystomatidae Schiner, 1862 | Picture-winged flies | 106 | Species | Taxom |
| Pleidae Fieber, 1817 | Pigmy backswimmers | 8 | Species | Taxom |
| Pleocomidae LeConte, 1861 | Rain beetle | 37 | Species | Taxom |
| Plokiophilidae China, 1953 | Spider web bug | 1 | Species | Taxom |
| Plumalexiidae Brothers, 2011 | | 1 | Species | Taxom |
| Plutellidae Guenée, 1845 | Diamond-back moths | 73 | Species | Taxom |
| Podoscirtidae Saussure, 1878 | | 54 | Species | Taxom |
| Polycentropodidae Ulmer, 1903 | Tube Maker Caddisflies | 160 | Species | Taxom |
| Polycreagridae Handlirsch, 1906 | | 1 | Species | Taxom |
| Polyctenidae Westwood, 1874 | Bat bugs | 3 | Species | Taxom |
| Polymitarcyidae Banks, 1900 | Pale Burrower Mayflies | 16 | Species | Taxom |
| Polyplacidae Fahrenholz, 1912 | Spiny rat lice | 39 | Species | Taxom |
| Polystoechotidae Handlirsch, 1906 | Giant lacewing | 5 | Species | Taxom |
| Polythoridae Munz, 1919 | Bannerwings | 3 | Species | Taxom |
| Pompilidae Latreille, 1805 | Pompilid wasps | 514 | Species | Taxom |
| Ponopterixidae Nel & al., 2014 | | 2 | Species | Taxom |
| Poroblattinidae Handlirsch, 1906 | | 12 | Species | Taxom |
| Potamanthidae Albarda, 1888 | Hacklegill mayflies | 6 | Species | Taxom |
| Prionoceridae Lacaordaire, 1857 | | 1 | Species | Taxom |
| Prionoglarididae Badonnel, 1951 | Large-winged Psocids | 6 | Species | Taxom |
| Prisopodidae Brunner von ..., 1893 | | 3 | Species | Taxom |
| Probnidae Sellards, 1909 | | 2 | Species | Taxom |
| Prochoropteridae Handlirsch, 1911 | | 1 | Species | Taxom |
| Procramptonomyiidae Kovalev, 1985 | | 2 | Species | Taxom |
| Proctotrupidae Latreille, 1802 | Proctotrupid wasps | 107 | Species | Taxom |
| Prodoxidae Riley, 1881 | Yucca Moths | 103 | Species | Taxom |
| Promastacidae Kevan & Wighton, 1981 | | 2 | Species | Taxom |
| Prophalangopsidae Saussure, 1878 | Grigs | 6 | Species | Taxom |
| Prosbolidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Proscopiidae Serville, 1838 | Jumping sticks | 1 | Species | Taxom |
| Prosechamyiidae Blagoderov &..., 2007 | | 2 | Species | Taxom |
| Prosopistomatidae Lameere, 1917 | | 6 | Species | Taxom |
| Prostomidae C. G. Thomson, 1859 | Jugular-horned beetle | 3 | Species | Taxom |
| Protelytridae Tillyard, 1931 | | 5 | Species | Taxom |
| Protembiidae Tillyard, 1937 | | 3 | Species | Taxom |
| Protereismatidae Lameere, 1917 | | 15 | Species | Taxom |
| Protohymenidae Tillyard, 1924 | | 13 | Species | Taxom |
| Protomeropidae Tillyard, 1926 | | 1 | Species | Taxom |
| Protoneuridae Tillyard, 1917 | Bambootails | 3 | Species | Taxom |
| Protophasmatidae Brongniart, 1885 | | 1 | Species | Taxom |
| Protophasmidae (Scudder, 1885) | | 1 | Species | Taxom |
| Protopsyllidiidae Becker-Migdi..., 1960 | | 1 | Species | Taxom |
| Protorhyphidae Handlirsch, 1906 | | 2 | Species | Taxom |
| Pruvostitidae Zalessky, 1929 | | 4 | Species | Taxom |
| Prygidae Aristov & Ra..., 2014 | | 1 | Species | Taxom |
| Pselaphidae (Lameere, 1900) | Short-winged mold beetles | 3 | Species | Taxom |
| Psephenidae Lacordaire, 1854 | Water pennies | 32 | Species | Taxom |
| Pseudocaeciliidae Pearman, 1936 | False Lizard Barklice | 19 | Species | Taxom |
| Pseudococcidae Heymons, 1915 | Mealy Bugs | 534 | Species | Taxom |
| Pseudophasmatidae Kirby, 1896 | Striped Walkingsticks | 14 | Species | Taxom |
| Pseudophyllodromiidae Hebard, 1929 | | 77 | Species | Taxom |
| Pseudopolycentropodidae Handlirsch, 1925 | | 2 | Species | Taxom |
| Pseudostigmatidae Tillyard, 1917 | Forest giants | 7 | Species | Taxom |
| Psilidae Macquart, 1835 | Carrot flies | 109 | Species | Taxom |
| Psilopsocidae Roesler, 1944 | | 1 | Species | Taxom |
| Psocidae Samouelle, 1819 | Common bark louse | 143 | Species | Taxom |
| Psocidiidae Tillyard, 1926 | | 8 | Species | Taxom |
| Psoquillidae Lienhard & S..., 2002 | Bird Nest Barklice | 19 | Species | Taxom |
| Psoropteridae Carpenter, 1977 | | 1 | Species | Taxom |
| Psychidae Boisduval, 1828 | Bagmoths | 79 | Species | Taxom |
| Psychodidae Newman, 1834 | Drain flies | 343 | Species | Taxom |
| Psychomyiidae Walker, 1852 | Net Tube Caddisflies | 35 | Species | Taxom |
| Psychopsidae Handlirsch, 1906 | Silky lacewing | 6 | Species | Taxom |
| Psyllidae Latreille, 1807 | Jumping plant lice | 459 | Species | Taxom |
| Psyllipsocidae Enderlein, 1903 | Cave Barklice | 29 | Species | Taxom |
| Pteridomylacridae Handlirsch, 1906 | | 2 | Species | Taxom |
| Pterolonchidae Meyrick, 1918 | Lance Wing Moths | 1 | Species | Taxom |
| Pteromalidae Dalman, 1820 | Pteromalid wasps | 916 | Species | Taxom |
| Pteronarcyidae Enderlein, 1909 | Giant stoneflies | 15 | Species | Taxom |
| Pterophoridae Zeller, 1841 | Plume Moths | 480 | Species | Taxom |
| Pthiridae Leach, 1817 | | 4 | Species | Taxom |
| Ptiliidae Heer, 1843 | Feather-wing beetles | 192 | Species | Taxom |
| Ptilodactylidae Laporte, 1836 | Ptilodactylid beetles | 54 | Species | Taxom |
| Ptiloneuridae Eertmoed, 1973 | | 10 | Species | Taxom |
| Ptinidae Latreille, 1802 | Death-watch and Spider Beetles | 693 | Species | Taxom |
| Ptychopteridae Osten Sacken, 1862 | Phantom crane flies | 26 | Species | Taxom |
| Pulicidae Billberg, 1820 | Cat fleas | 50 | Species | Taxom |
| Putoidae Beardsley, 1969 | Giant mealybugs | 31 | Species | Taxom |
| Pygidicranidae (Verhoeff, 1902) | | 3 | Species | Taxom |
| Pygiopsyllidae Wagner, 1939 | | 6 | Species | Taxom |
| Pyralidae Latreille, 1802 | Flour Moths | 1367 | Species | Taxom |
| Pyrgomorphidae Brunner von ..., 1874 | Bushlocusts | 40 | Species | Taxom |
| Pyrgotidae Schiner, 1868 | Light Flies | 20 | Species | Taxom |
| Pyrochroidae Latreille, 1807 | Cardinal beetles | 71 | Species | Taxom |
| Pyrrhocoridae Dohrn, 1859 | Cotton stainers | 16 | Species | Taxom |
| Pythidae Solier, 1834 | Dead log bark beetles | 10 | Species | Taxom |
| Raaschiidae Beckemeyer, 2004 | | 1 | Species | Taxom |
| Rafaelianidae Engel & Nel, 2017 | | 0 | Species | Taxom |
| Rangomaramidae Jaschhof & D..., 2002 | | 2 | Species | Taxom |
| Raphidiidae Latreille, 1810 | Raphidiid snakeflies | 38 | Species | Taxom |
| Raphidiomimidae Vishniakova, 1973 | | 0 | Species | Taxom |
| Reduviidae Latreille, 1807 | Assassin and thread-legged bugs | 424 | Species | Taxom |
| Rhachiberothidae Tjeder, 1959 | Thorny lacewing | 3 | Species | Taxom |
| Rhagionidae Latreille, 1802 | Snipe flies | 194 | Species | Taxom |
| Rhaphidiopsidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Rhaphidophoridae Walker, 1869 | And Cave Weta | 196 | Species | Taxom |
| Rhiniidae Brauer & Ber..., 1889 | | 1 | Species | Taxom |
| Rhinophoridae Robineau-Des..., 1863 | Woodlouse flies | 24 | Species | Taxom |
| Rhinotermitidae Froggatt, 1897 | Subterranean termites | 42 | Species | Taxom |
| Rhipiceridae Latreille, 1834 | Cedar beetles | 9 | Species | Taxom |
| Rhipiphoridae Gemminger & ..., 1870 | Hump back beetles | 39 | Species | Taxom |
| Rhizoecidae Williams, 1969 | | 60 | Species | Taxom |
| Rhopalidae Amyot & Serv..., 1843 | Rhopalid Bugs | 70 | Species | Taxom |
| Rhopalopsyllidae Oudemans, 1909 | Marsupial fleas | 17 | Species | Taxom |
| Rhopalosomatidae Ashmead, 1896 | Rhopalosomatid wasps | 9 | Species | Taxom |
| Rhyacophilidae Stephens, 1836 | Free-living Caddisflies | 2 | Species | Taxom |
| Rhynchitidae Gistel, 1848 | Leaf-rolling weevils | 24 | Species | Taxom |
| Rhyparochromidae Amyot & Serv..., 1843 | Dirt-colored Seed Bugs | 316 | Species | Taxom |
| Rhyphidae (Newman, 1834) | | 0 | Species | Taxom |
| Ricaniidae Amyot & Audi..., 1843 | | 10 | Species | Taxom |
| Richardidae Snow, 1896 | Richardid flies | 34 | Species | Taxom |
| Richardiidae (Snow, 1896) | Picture-winged flies | 9 | Species | Taxom |
| Ricinidae Neumann, 1890 | | 37 | Species | Taxom |
| Riodinidae Grote, 1895 | Metalmark Butterflies | 356 | Species | Taxom |
| Ripiphoridae Gemminger & ..., 1870 | Rhipiphoridae | 59 | Species | Taxom |
| Ripipterygidae Ander, 1939 | Mud crickets | 8 | Species | Taxom |
| Roeslerstammiidae Bruand, 1850 | Double-eye moths | 1 | Species | Taxom |
| Romaleidae Brunner von ..., 1893 | Lubber grasshopper | 55 | Species | Taxom |
| Ropalomeridae Linder, 1930 | Ropalomerid flies | 9 | Species | Taxom |
| Roproniidae Bradley, 1905 | Roproniid wasps | 3 | Species | Taxom |
| Rossianidae Gall, 1996 | | 1 | Species | Taxom |
| Rutelidae (MacLeay, 1819) | | 104 | Species | Taxom |
| Saldidae Amyot and Se..., 1843 | Shore bug | 110 | Species | Taxom |
| Salpingidae Leach, 1815 | Narrow-waisted bark beetle | 52 | Species | Taxom |
| Sapygidae Latreille, 1810 | Club-horned wasps | 23 | Species | Taxom |
| Sarcophagidae Macquart, 1834 | Flesh flies | 882 | Species | Taxom |
| Saturniidae Boisduval, 1837 | And Giant Silk Moths | 407 | Species | Taxom |
| Scarabaeidae Latreille, 1802 | Dung beetles | 4808 | Species | Taxom |
| Scathophagidae Robineau-Des..., 1830 | Dung flies | 225 | Species | Taxom |
| Scatopsidae Newman, 1834 | Dung midges | 144 | Species | Taxom |
| Scelionidae Haliday, 1839 | Scelionid wasps | 574 | Species | Taxom |
| Scenopinidae Burmeister, 1835 | Window Flies | 169 | Species | Taxom |
| Schizoblattidae Durden, 1969 | | 15 | Species | Taxom |
| Schizopodidae (LeConte, 1859) | False Jewel Beetles | 8 | Species | Taxom |
| Schizopteridae Reuter, 1891 | Jumping ground bugs | 20 | Species | Taxom |
| Schreckensteiniidae Fletcher, 1929 | Bristle Legged Moths | 4 | Species | Taxom |
| Sciadoceridae (Schmitz, 1929) | | 1 | Species | Taxom |
| Sciaridae Billberg, 1820 | Black fungus gnats | 21 | Species | Taxom |
| Sciomyzidae Fallen, 1820 | Marsh Flies | 283 | Species | Taxom |
| Scirtidae Fleming, 1821 | Marsh Beetle | 108 | Species | Taxom |
| Sclerogibbidae Ashmead, 1902 | Sclerogibbid wasp | 4 | Species | Taxom |
| Scolebythidae Evans, 1963 | Scolebythid wasps | 5 | Species | Taxom |
| Scoliidae Leach, 1815 | Mammoth wasps | 36 | Species | Taxom |
| Scolytidae (Latreille, 1807) | Ambrosia | 3 | Species | Taxom |
| Scraptiidae Mulsant, 1856 | Antlike leaf beetles | 61 | Species | Taxom |
| Scutelleridae Leach, 1815 | Jewel bugs | 55 | Species | Taxom |
| Scydmaenidae (Leach, 1815) | Ant-like stone beetles | 518 | Species | Taxom |
| Scythrididae Rebel, 1901 | Flower Moths | 3 | Species | Taxom |
| Scytinopteridae Handlirsch, 1906 | | 1 | Species | Taxom |
| Sematuridae Guenée, 1858 | American Swallowtail Moths | 9 | Species | Taxom |
| Sepsidae Walker, 1833 | Black scavenger flies | 75 | Species | Taxom |
| Sepulcidae Rasnitsyn, 1968 | | 1 | Species | Taxom |
| Serendipidae Evenhuis, 1994 | | 0 | Species | Taxom |
| Sericostomatidae Stephens, 1836 | Bushtailed Caddisflies | 17 | Species | Taxom |
| Serpentivenidae Shcherbakov, 1984 | | 1 | Species | Taxom |
| Serphitidae Brues, 1937 | | 9 | Species | Taxom |
| Sesiidae Boisduval, 1828 | Clear Wings | 294 | Species | Taxom |
| Sialidae Leach, 1815 | Alderflies | 33 | Species | Taxom |
| Sierolomorphidae Krombein, 1951 | Sierolomorphid wasp | 8 | Species | Taxom |
| Signiphoridae Howard, 1894 | Signiphorid waps | 48 | Species | Taxom |
| Silphidae Latreille, 1807 | Burying And Carrion Beetles | 99 | Species | Taxom |
| Silvanidae Kirby, 1837 | Flat bark beetles | 89 | Species | Taxom |
| Simuliidae Newman, 1834 | Black flies | 405 | Species | Taxom |
| Siphlonuridae Banks, 1900 | Primitive Minnow Mayflies | 81 | Species | Taxom |
| Siricidae Billberg, 1820 | Horntail | 36 | Species | Taxom |
| Sisyridae Handlirsch, 1908 | Spongeflies | 10 | Species | Taxom |
| Smicripidae Horn, 1879 | Palmetto beetle | 2 | Species | Taxom |
| Sojanoraphidiidae Martynova, 1952 | | 1 | Species | Taxom |
| Spanioderidae Handlirsch, 1906 | | 9 | Species | Taxom |
| Spathiopterygidae Engel & Orte..., 2013 | | 1 | Species | Taxom |
| Sphaeritidae Schuckard, 1839 | False clown beetle | 1 | Species | Taxom |
| Sphaeriusidae Erichson, 1845 | Minute Bog Beetles | 4 | Species | Taxom |
| Sphaeroceridae Macquart, 1835 | Dung flies | 418 | Species | Taxom |
| Sphaeropsocidae Kolbe, 1883 | | 3 | Species | Taxom |
| Sphecidae Latreille, 1802 | Digger & Sand wasps | 237 | Species | Taxom |
| Sphindidae Jacquelin du..., 1860 | Cryptic slime mold beetle | 12 | Species | Taxom |
| Sphingidae Latreille, 1802 | Hawk Moths | 422 | Species | Taxom |
| Spilapteridae Brongniart, 1894 | | 4 | Species | Taxom |
| Spiloblattinidae Handlirsch, 1906 | | 50 | Species | Taxom |
| Spiralizoridae Kocarek, Ho..., 2020 | | 2 | Species | Taxom |
| Spongiphoridae Verhoeff, 1902 | Little Earwigs | 6 | Species | Taxom |
| Spurostigmatidae Casasola Gon..., 2006 | | 3 | Species | Taxom |
| Srokalarvidae Haug & al., 2016 | | 1 | Species | Taxom |
| Staphylinidae Lameere, 1900 | Rove beetles | 8496 | Species | Taxom |
| Steingeliidae Morrison, 1927 | | 4 | Species | Taxom |
| Stenopelmatidae Burmeister, 1838 | Bulldog Raspy Crickets | 31 | Species | Taxom |
| Stenopsocidae Pearman, 1936 | Narrow Barklice | 2 | Species | Taxom |
| Stenopsychidae Martynov, 1924 | | 1 | Species | Taxom |
| Stenotrachelidae C. G. Thomson, 1859 | False long-horned beetles | 19 | Species | Taxom |
| Stephanidae Leach, 1815 | Crown wasp | 20 | Species | Taxom |
| Stereopteridae Carpenter, 1950 | | 3 | Species | Taxom |
| Stigmacoccidae Morrison giv..., 2006 | | 1 | Species | Taxom |
| Stigmaphronidae Kozlov, 1975 | Stigmaphronid wasps | 9 | Species | Taxom |
| Stivaliidae Mardon, 1978 | | 2 | Species | Taxom |
| Stolamissidae Liu & Engel, 2007 | | 1 | Species | Taxom |
| Stratiomyidae Latreille, 1802 | Soldier flies | 640 | Species | Taxom |
| Streblidae (Kolenati, 1863) | Bat flies | 21 | Species | Taxom |
| Strephocladidae Martynov, 1938 | | 1 | Species | Taxom |
| Strongylophthalmyiidae Hennig, 1940 | Strongylophthalmyiid flies | 6 | Species | Taxom |
| Styloperlidae Illies, 1966 | | 2 | Species | Taxom |
| Stylopidae Kirby, 1813 | Strepsiptera | 135 | Species | Taxom |
| Susumaniidae Gorochov, 1988 | | 1 | Species | Taxom |
| Sylvabestiidae Aristov, 2000 | | 1 | Species | Taxom |
| Synchroidae Lacordaire, 1859 | Synchroa bark beetles | 1 | Species | Taxom |
| Synteliidae Lewis, 1882 | | 2 | Species | Taxom |
| Syntomidae (Herrich Scha..., 1846) | | 2 | Species | Taxom |
| Syntonopteridae Handlirsch, 1911 | | 3 | Species | Taxom |
| Syringogastridae Prado, 1969 | | 4 | Species | Taxom |
| Syrphidae Latreille, 1802 | Drone flies | 1775 | Species | Taxom |
| Tabanidae Latreille, 1802 | Breeze flies | 764 | Species | Taxom |
| Tachardiidae Green, 1896 | Lac insects | 14 | Species | Taxom |
| Tachinidae (Robineau-Des..., 1830) | Bristle Flies | 3187 | Species | Taxom |
| Taeniopterygidae Klapálek, 1905 | Taeniopterygid winter stoneflies | 51 | Species | Taxom |
| Tanaoceridae Rehn, 1948 | Desert Long-horned Grasshoppers | 4 | Species | Taxom |
| Tanaostigmatidae Howard, 1890 | Tanaostigmatid wasps | 32 | Species | Taxom |
| Tanyderidae Alexander, 1919 | Primitive crane flies | 5 | Species | Taxom |
| Tanypezidae Rondani, 1856 | Stretched-foot flies | 5 | Species | Taxom |
| Tarachodidae Handlirsch, 1930 | | 1 | Species | Taxom |
| Tasimiidae Riek, 1968 | | 1 | Species | Taxom |
| Telegeusidae (LeConte, 1861) | Glowworm beetles | 16 | Species | Taxom |
| Tenebrionidae Latreille, 1802 | Darkling Beetle | 2585 | Species | Taxom |
| Teneopteridae (Richardson, 1956) | | 1 | Species | Taxom |
| Tenthredinidae Latreille, 1804 | Common sawflies | 940 | Species | Taxom |
| Tephritidae Newman, 1834 | Fruit flies | 864 | Species | Taxom |
| Teratembiidae Krauss, 1911 | | 14 | Species | Taxom |
| Teredidae Seidlitz, 1888 | | 6 | Species | Taxom |
| Termitaphididae Myers, 1924 | Termite bug | 2 | Species | Taxom |
| Termitidae Latreille, 1802 | Higher termites | 61 | Species | Taxom |
| Termopsidae Grassé, 1949 | Damp wood termite | 6 | Species | Taxom |
| Tessaratomidae Stål, 1864 | Giant shield bug | 1 | Species | Taxom |
| Tethinidae (Hendel, 1916) | Tethinid flies | 57 | Species | Taxom |
| Tetracampidae Förster, 1856 | Tetracampid wasps | 10 | Species | Taxom |
| Tetratomidae Billberg, 1820 | Polypore fungus beetle | 52 | Species | Taxom |
| Tetrigidae Rambur, 1838 | Groundhoppers | 80 | Species | Taxom |
| Tettigarctidae Distant, 1905 | Hairy cicada | 1 | Species | Taxom |
| Tettigometridae Germar, 1821 | | 1 | Species | Taxom |
| Tettigoniidae Krauss, 1902 | Bush crickets | 739 | Species | Taxom |
| Thanerocleridae Chapin, 1921 | | 5 | Species | Taxom |
| Thaumaleidae Bezzi, 1913 | Solitary midges | 35 | Species | Taxom |
| Thaumastocoridae Kirkaldy, 1908 | Palm bug | 2 | Species | Taxom |
| Thaumatoneuridae Fraser, 1957 | | 7 | Species | Taxom |
| Therevidae Newman, 1834 | Stiletto flies | 377 | Species | Taxom |
| Thericleidae Burr, 1899 | | 1 | Species | Taxom |
| Thespidae Giglio-Tos, 1919 | | 17 | Species | Taxom |
| Thripidae Stevens, 1829 | Common thrips | 692 | Species | Taxom |
| Throscidae Laporte, 1840 | False metallic wood-boring beetles | 33 | Species | Taxom |
| Thueringoedischiidae Zessin, 1997 | | 1 | Species | Taxom |
| Thynnidae Shuckard, 1841 | Thynnid Wasps | 8 | Species | Taxom |
| Thyreocoridae Amyot and Se..., 1843 | Black bugs | 54 | Species | Taxom |
| Thyrididae Herrich-Schä..., 1846 | Picture Winged Leaf Moths | 42 | Species | Taxom |
| Timematidae Caudell, 1903 | Timemas | 27 | Species | Taxom |
| Tineidae Latreille, 1810 | & Allies | 523 | Species | Taxom |
| Tingidae Laporte, 1832 | Lace bug | 288 | Species | Taxom |
| Tiphiidae Leach, 1815 | Flower wasps | 332 | Species | Taxom |
| Tipulidae Latreille, 1802 | Crane Flies | 2660 | Species | Taxom |
| Tischeriidae Spuler, 1898 | Lyonetiid moths | 116 | Species | Taxom |
| Tococladidae Carpenter, 1966 | | 3 | Species | Taxom |
| Tortricidae Latreille, 1803 | Bell Moths | 3382 | Species | Taxom |
| Torymidae Walker, 1833 | Apple seed chalcids | 382 | Species | Taxom |
| Trachopterygidae Carpenter, 1976 | | 1 | Species | Taxom |
| Trachypachidae C. G. Thomson, 1857 | False ground beetle | 11 | Species | Taxom |
| Triassoblattidae Durden, 1969 | | 2 | Species | Taxom |
| Trichoceridae Rondani, 1841 | Winter Crane Flies | 44 | Species | Taxom |
| Trichodectidae Kellogg, 1896 | | 168 | Species | Taxom |
| Trichogrammatidae Haliday, 1851 | Trichogrammatid wasps | 163 | Species | Taxom |
| Trichopsocidae Pearman, 1936 | Lash-faced psocid | 4 | Species | Taxom |
| Tricorythidae Lestage, 1942 | Little stout crawler mayflies | 0 | Species | Taxom |
| Tridactylidae Saussure, 1874 | Pygmy mole cricket | 15 | Species | Taxom |
| Trigonalidae (Cresson, 1887) | Trigonalid sawflies | 7 | Species | Taxom |
| Trigonidiidae (Saussure, 1870) | And Ground Crickets | 90 | Species | Taxom |
| Trimenoponidae Harrison, 1916 | | 2 | Species | Taxom |
| Triozidae Löw, 1879 | Jumping plant lice | 98 | Species | Taxom |
| Tristiridae Rehn, 1906 | | 2 | Species | Taxom |
| Troctopsocidae Mockford, 1967 | | 4 | Species | Taxom |
| Trogidae (MacLeay, 1819) | Gnawer beetles | 105 | Species | Taxom |
| Trogiidae Enderlein, 1903 | Granary Booklice | 18 | Species | Taxom |
| Trogossitidae Latreille, 1802 | Bark gnawing beetle | 121 | Species | Taxom |
| Tropiduchidae Stål, 1866 | Tropiduchid Planthoppers | 22 | Species | Taxom |
| Tshekardocoleidae Rohdendorf, 1944 | | 1 | Species | Taxom |
| Uenoidae Iwata, 1927 | Stonecase Caddisflies | 19 | Species | Taxom |
| Ulidiidae Macquart, 1835 | Picture-winged Flies | 35 | Species | Taxom |
| Umenocoleidae Chen & Tian, 1973 | | 2 | Species | Taxom |
| Uraniidae Blanchard, 1845 | Swallowtail Moths | 42 | Species | Taxom |
| Urodidae Kyrki, 1984 | False Burnet Moths | 6 | Species | Taxom |
| Urolibellulidae Zeiri & al., 2015 | | 1 | Species | Taxom |
| Vanhorniidae Crawford, 1909 | Vanhorniid wasps | 1 | Species | Taxom |
| Veliidae Amyot & Serv..., 1843 | Broad-shouldered bugs | 86 | Species | Taxom |
| Vermileonidae Williston, 1886 | Wormlion | 5 | Species | Taxom |
| Vermipsyllidae Wagner, 1889 | Carnivore fleas | 8 | Species | Taxom |
| Vesperidae Mulsant, 1839 | Vesperid longicorn beetles | 5 | Species | Taxom |
| Vespidae Leach, 1815 | And Allies | 771 | Species | Taxom |
| Vitimiidae Sharov, 1968 | | 0 | Species | Taxom |
| Xenidae Pohl & Beutel, 2005 | | 34 | Species | Taxom |
| Xenoblattidae Durden, 1969 | | 5 | Species | Taxom |
| Xiphocentronidae Schmid, 1982 | | 21 | Species | Taxom |
| Xiphydriidae Leach, 1819 | Wood wasps | 12 | Species | Taxom |
| Xyelidae Newman, 1835 | Sawfly | 56 | Species | Taxom |
| Xylococcidae (Pergrande, 1898) | | 5 | Species | Taxom |
| Xylomyidae Verrall, 1901 | Wood soldier flies | 30 | Species | Taxom |
| Xylophagidae Fallen, 1810 | Awl-flies | 35 | Species | Taxom |
| Xyloryctidae Meyrick, 1890 | Flower Moths | 94 | Species | Taxom |
| Xyronotidae Bolivar, 1909 | Razor-backed bush-hoppers | 4 | Species | Taxom |
| Yponomeutidae Stephens, 1829 | Ermine Moths | 158 | Species | Taxom |
| Ypsolophidae Guenée, 1845 | Ypsolophid Moths | 69 | Species | Taxom |
| Zacallitidae Cockerell, 1928 | Extinct family of damselflies | 1 | Species | Taxom |
| Zopheridae Solier, 1834 | Cylindrical bark beetles | 274 | Species | Taxom |
| Zorotypidae Silvestri, 1913 | Angel insects | 5 | Species | Taxom |
| Zygaenidae Latreille, 1809 | Burnet Forester | 108 | Species | Taxom |
