The Choanata are a taxon in which the extinct osteolepiformes , the lung fish (Dipnoi) and the terrestrial vertebrates (Tetrapoda) are grouped together. Their common feature is a connection from the nose to the throat, the choane . But since the Dipnoer are probably more closely related to the Porolepiformes , the Choanata are evidently paraphyletic . This meant that the Dipnoer Choanen would have emerged convergent . In addition, the origin of the Choane is still the subject of scientific discussions. It could be the rear, outer nostril (narine) that has migrated into the mouth or newly created, additional openings in the roof of the mouth. For both variants there are parallels with the Teleostei (see fish nose ).
