104Amniota104Archosauria104Dinosauria104Ornithischia104Thyreophora104Ornithopoda104Styracosterna104Marginocephalia104Ceratopsidae104Saurischia104Sauropodomorpha104Neosauropoda104Neotheropoda104Coelurosauria104EumaniraptoraAMNIOTAReptiliaParareptiliaDiapsida??ArchosauriaAmphibiaTetrapodaSynapsidaDimetrodonTherapsidaTestudinesMammaliaAmniotic egg; Claws; Live on land for entire life cycleLimbs with digits; Necks; Live on land as adultsAMNIOTASauriaArchosauromorphaArchosauriformesMesosaurusPetrolacosaurusEuparkeriaDicynodontiaPareiasauriaEuryapsidaSauropterygiaPlesiosauriaIchthyosauriaPlacodontiaLepidosauriaThrinaxodonAglandular skin; Water-conserving kidneys; enhanced color visionInfra- and Supratemporal fenestrae; Hindlimbs more powerful than forelimbsAntorbital and man-dibular fenestrae; air sac system?; Belly-breathing?Infratemporal fenestraEnlarged ITF; Incisors, canines & cheek teeth; Forelimbs more devel-oped than hindARCHOSAURIAAvemetatarsaliaSuchiaParacrocodylomorphaLoricataOrnithodiraDinosauromorphaDinosauriformes?DinosauriaArchosauriformesCrurotarsiCrocodylomorphaNests with vegetation; Parental care of young; parasagittal stance?; one-way flow-through lungsAntorbital and mandibular fenestrae; air sac system?; Belly-breathing?ARCHOSAURIALagerpetidaeEuparkeriaPhytosauriaScleromochlusMarasuchusSilesauridaePterosauriaAetosauriaPoposauroideaElongate tibiae and metatarsi; loss of body armorNeck with S-shaped curveParasagittal stance?; hinge-like ankle jointElongate pubes and ischia?RauisuchoideaSilesauridaeSauropodomorphaTheropodaSaurischiaDINOSAURIAOrnithischiaSemiopposable Manual Digit I; Reduced Manual Digits IV & V; Open (perforate) AcetabulumDINOSAURIAMarginocephaliaOrnithopodaThyreophoraMarginocephaliaNeornithischiaGenasauriaORNITHISCHIADinosauriaBroad Leaf-shaped Teeth with Large Denticles; Predentary Bone; 5 or more sacralsBackwards-pointing Pubis; Epaxial ossified tendons; Inset tooth row (for cheeks?)ORNITHISCHIAOrnithopodaHeterodontosauridaeThyreophoraPisanosaurusSaurischiaEocursorAsymmetrical enamel on teethDeep powerful skulls; Premaxillary tooth row ventral to maxillary tooth row; Jaw joint ventral to dentary tooth rowHands reduced in size and reduced grasping abilityTHYREOPHORAOrnithischiaPaired plates and spikes; ThagomizerOsteodermsTHYREOPHORANeornithischiaStegosaurinaeEurypodaNodosauridaeSauropeltaEdmontoniaAnkylosauridaeStegosauriaAnkylosauriaHuayangosauridaeScutellosaurusScelidosaurusDacentrurinaeStegosaurinaeGastoniaPinacosaurusEuoplocephalusLarger size; Heavier armor; Obligate quadrupedalityOsteoderms fused to skull; Rings of osteoderms on neck and shoul-der; Extensive osteoderms over body; Wide across bodyShort triangular head; Triangular hornlets on skull; Complex nasal chambers; Tail clubORNITHOPODAIguanodontiaAnkylopollexiaDryomorphaNeornithischiaGenasauriaGreatly enlarged nares; much larger size; Spike thumb; metacarpals II-IV hoof-like; metacar-pal V opposablePremaxillary lower margin ventral to maxillary tooth row; Mandibular articulation ventral to dentary tooth row; Pleurokinetic hinge joint in craniumMarginocephaliaStyracosternaCamptosaurusHypsilophodontidaeThescelosauridaeRhabdodontidaeTenontosaurusDryosauridaeOthnielosaurusLarger size; Premaxilla toothless; Enlarged naris; 6 or more sacralsWell-developed pleurokinetic hingeORNITHOPODASTYRACOSTERNAAnkylopollexiaGreatly enlarged nares; much larger size; Spike thumb; Metacarpals II-IV hoof-like; Metacarpal V opposableHadrosauridaeHadrosauriaSaurolophinaeCamptosauridaeIguanodonOuranosaurusProtohadrosCorythosaurusParasaurolophusGryposaurusAnatotitanLambeosaurinaeEnd of premaxillae flare outwards (”duckbill”); Increased number of teeth; Dental battery; Manual digit I lost; Metacarpals II-IV greatly elongatedExtremely enlarged nares; Greatly flared snoutHollow nasal chamber forming crest on top of headSTYRACOSTERNAMARGINOCEPHALIACoronosauriaCeratopsoideaCeratopsiaNeoceratopsiaRostral bone; Jugals form pointed “horns”CeratopsidaeOrnithopodaPachycephalosauriaPachycephalosaurusGenasauriaStegocerasPsittacosauridaeArchaeoceratopsZuniceratopsProtoceratopsidaeLeptoceratopsidaeLarger size; Postorbital hornsEven larger size; Nasal horn; Shearing dental batteryThickened skull roof; Small ossifi-cations along ridge of skullEnlarged frill; Enlarged skull; Obligate quadrupedalityShelf of bone extending back over occipital region of skullFrillDomeQuadrupedalityMARGINOCEPHALIAZuniceratopsAlbertaceratopsCentrosaurusStyracosaurusAnchiceratopsTriceratopsCERATOPSIDAECeratopsoideaChasmosaurinaeCentrosaurinaeLonger shallower snouts; Elongated rostral; Long frillsCERATOPSIDAELarger size; Postorbital hornsShort, deep snout; pair of spikes projecting from back of frillNasal horns enlarged; postorbital horns reducedEven larger size; Nasal horn; Shearing dental batteryOrnithischiaHerrerasauriaEodromaeusTawaSauropodomorphaTheropodaSAURISCHIADinosauriaSpecial Articulations (hyposphene-hypantrum) in dorsal vertebrae; Elongated Neck; Hollow air sac chambers in cervicals; Metacarpal I reduced; Enlarged thumb claw; Manual Digit II longest in the manusSAURISCHIANeotheropodaBlade-like serrated teeth; Promaxillary fenestra; Intramandibular joint; Enlarged hands with increased grasping abilityPremaxilla-maxilla kink“basal theropods”EfraasiaAntetonitrusMamenchisauridaeCetiosauridaeShunosaurusPlateosauridaeRiojasauridaeMassospondylidaePlateosauriaMassopodaAnchisauriaEusauropoda“core prosauropods”GuaibasauridaeTheropodaSaurischiaSAUROPODOMORPHASauropodaNeosauropodaDecreased skull size; tall leaf-shaped teeth; long neck; possible small beak on dentarySAUROPODOMORPHAMelanorosauridaeCheeks?Increased body size; even longer neck; shortened distal hindlimbFurther size increase; some quadrupeality Shortened snout; obligate quadrupeality Teeth at front of snout; Nares dorsally placed; Columnar metacarpusFrurther size increase; 12 or more cervicals; Modified manus and pedes Vulcanodontidae“basalsauropodomorphs”Rounded snout; tooth-to-tooth occlusion; wide gape (loss of cheeks?)QuadrupealityJobariaDiplodocidaeDiplodocoideaFlagellicaudataRebbachisauridaeEusauropodaNEOSAUROPODAMacronariaLithostrotiaAntarctosauridaeLognkosauriaTitanosauriformesEutitanosauriaTitanosauriaTeeth concentrated at front of jaws; Nares even more dorsally placed; Columnar metacarpusNEOSAUROPODAAstrodonBrachiosauridaeDicraeosauridaePencil-shaped teeth only along front of snout; Squared-off snoutNares joined together above orbit; Long skulls; Short