This taxonomy of the Subphylum Hexapoda has 3 classes.  Brusca and Brusca (2003) lump the collembolans, proturans and diplurans into a single class that they call Entognatha.  However, even they conclude that the diplurans likely are convergent in their major characters (especially the mouthparts on which the group is defined).  Therefore, I believe that the diplurans should be separated into a different class.  So, I have used the taxonomy of Hales (2001) for the collembolans, proturans and diplurans and divided them into two classes (see below).  The taxonomy of the Class Insecta, however, follows the system of Brusca and Brusca (2003).  


Small; wingless; mouth entognathous (base of mouthparts within head capsule); mandibles with single articulation; legs with one tarsus (not articulated); with or without tracheae; abdomen 6 segments (colembolans) or 11 segments (proturans).

Entomobrya, Achorutes.




Small;  no wings; no eyes; no external genitalia and no Malpighian tubules; mouthparts entognathous; mandible with single articulation, rolling action, abdomen 11-segmented when embryonic, fewer when mature, gonopores on 9th segment; 7 pairs of abdominal styli, 1 pair of cerci, up to 7 pairs of abdominal spiracles.

Campodea, Japyx.




Wingless; ocelli and compound eyes (contiguous); body scaly; mandibles with single articulation; tarsi with 3 articulated segments; some legs with exites (not uniramous); abdomen with "leglets" on segments; caudal filaments. Jumping bristletails.


Wingless; mouthparts ectognathous, mandible with 2 articulations; hypopharynx with 1 lobe; head with clypeus and clypeofrontal sulcus; small maxillary palps; only basal scape of antennae with muscles; abdomen 11-segmented with 3-8 pairs of styli; tergum of 11th segment prolonged into articulated cercal filaments of equivalent length; female gonopores on 8th segment, male gonopores on 10th; without ocelli; reduced compound eyes; without copulatory organs; thoracic and abdominal segments with well-developed transverse tendon system ventral; tracheal system complex, with longitudinal trunks, molting continues after maturity.

Lepisma, Thermobia.


One pair of wings (unless lost) on both 2nd and 3rd thoracic segments; ectognathous mouthparts; mandible with 2 articulations; hypopharynx with 1 lobe; maxillary palps small; head with clypeus and clypeofrontal sulcus; only basal scape of antennae with muscles; without abdominal styli except on genital segments; female gonopores on 8th segment, male gonopores on 10th; copulation occurs, female often with ovipositor, eggs with amnion and chorion; epicuticle waterproof; without transverse tendon system in thoracic or abdominal segments; molting ceases at maturity.

Subclass Hemimetabola: Gryllus, Anisomorpha, Periplaneta, Stagomomantis, Tetrix, Microcentrum, Gryllotalpa, Forficula, Perla, Pteronarcys, Reticulotermes, Kalotermes, Macrotermes, Embia, Pararhagadochir, Gynembia, Gomphus, Anax, Libellula, Lestes, Agrion, Argia, Ephemera, Hexagenia, Potamanthus, Baetis, Menopon, Goniodes, Trichodectes, Pediculus, Phthirius, Psocus, Psocathropos, Trogium, Atropos, Hercothrips, Heliothrips, Thrips, Zorotypus, Leptocoris, Murgantia, Pangaeus, Eurygaster, Nezara, Anasa, Blissus, Corythucha, Phymata, Arilus, Nabis, Cimex, Orius, Lygus, Halticus, Gerris, Gelastocoris Ranatra, Lethocerus, Notonecta, Arctocorixa, Scolops, Magicicada, Ceresa, Aphrophora, Graphocephala, Oncometopia, Paratrioza, Trialeurodes, Myzus, Pseudococcus, Icerya, Lepidosaphes.

Subclass Holometabola: Panorpa, Bittacus, Hydropsyche, Helicopsyche, Rhyacophila, Goera, Corydalus, Chrysopa, Myrmeleon, Coleophora, Tinea, Tineola, Plutella, Sanninoidea, Gnorimoschema, Carpocapsa, Polychrosis, Archips, Pyrausta, Loxostege, Hypsopygia, Crambus, Diatraea, Plodia, Thridopteryx, Estigmene, Hyphantria, Catocala, Trichoplusia, Agrotis, Heliothis, Datana, Hemerocampa, Protoparce, Alsophila, Synchlora, Malacosoma, Samia, Tropaea, Proteides, Polites, Iphiclides, Colias, Danaus, Minois, Vanessa, Phycoides, Lycaenopsis, Lycaena, Atlides, Cicendela, Calosoma, Harpalus, Dytiscus, Dineutes, Hydrophilus, Silpha, Paederus, Hister, Calopteron, Photinus, Chauliognathus, Enoclerus, Agriotes, Chrysobothris, Dermestes, Adalia, Mordellistena, Epicauta, Alobates, Tribolium, Lyctus, Amphicerus, Ptinus, Canthon, Phyllophaga, Popilius, Pseudoleucanus, Saperda, Leptinotarsa, Altica, Callosobruchus, Cylas, Pulex, Ctenocephalides, Xenosylla, Tipula, Aedes, Simulium, Tendipes, Phytophaga, Stratiomys, Tabanus, Chrysops Rhagio, Bombylius, Asilus, Diploneura, Drosophila, Liriomyza, Musca, Oestrus, Sarcophaga, Xenos, Stylops, Caliroa, Tremex, Megarhyssa, Macrocentrus, Torymus, Harmolita, Trichogramma, Scelio, Pelecinus, Formica, Campototus, Pepsis, Polistes, Bembix, Colletes, Halictus, Bombus, Apis.



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By Jack R. Holt and Carlos A. Iudica.  Last revised: 02/04/2012