An kuma ba da shawarar cewa Dinosauria za a bayyana shi dangane da MRCA na Megalosaurus da Iguanodon, saboda waɗannan su ne biyu daga cikin jinsuna uku da Richard Owen ya ambata lokacin da ya gane Dinosauria. Dukkanin ma'anar biyu sun haifar da nau'ikan dabbobi guda ɗaya da aka bayyana a matsayin dinosaur: "Dinosauria = Ornithischia + Saurischia", wanda ya ƙunshi ankylopoposaurians (armored herbivorous quadruped), stegoposaurians (plated herbivorous quadrupeds), ceratopsians (herbivorous quadrupeds tare da horns da horns), da kuma dukkan zuriyarsa.
mafi kwanan nan magabata (MRCA) na Triceratops da Neornithes, da duk zuriyarsa