Morganucodon is a genus which lived during the Upper Triassic in Wales(England) and east Asia, maybe even South Africa. It is unclear where those animals should be classified. Sometimes it was classified as a member of Eucynodonts (a mammal like reptile group), sometimes it was classified as a primitive mammal in the subclass of Prototheria, ordo Doconta(extinct) or Tricodonta. What makes Morganucodon special is that some of its upper jaw reminds reptiles a lot. Inscisives are are not placed in the Preamaxillaria (like mammals), but the Maxillaria (like some specialized Therapsida. The lower jaw has only reptile elements. More research is needed to find out more about this species.