Archaeopteryx of Avialae (defined by the authors as the most inclusive clade containing "Passer domesticus", but not "Dromaeosaurus albertensis" or "Troodon formosus"). "Archaeopteryx" was found to form a grade at the base of Avialae with "Xiaotingia", "Anchiornis", and "Aurornis". Compared to "Archaeopteryx", "Xiaotingia" was found to be more closely related to extant birds, while both "Anchiornis" and "Aurornis" were found to be more distantly so. Archaeopteryx Archaeopteryx (), meaning "old wing" (sometimes referred to by its German name ("original bird" or "first bird")), is a genus of bird-like dinosaurs that is transitional between non-avian feathered dinosaurs and modern birds. The name
Archaeopteryx be given preference over "lithographica" in instances where scientists considered them to represent the same species. It has been noted that the feather, the first specimen of "Archaeopteryx" described, does not correspond well with the flight-related feathers of "Archaeopteryx". It certainly is a flight feather of a contemporary species, but its size and proportions indicate that it may belong to another, smaller species of feathered theropod, of which only this feather is known so far. As the feather had been designated the type specimen, the name "Archaeopteryx" should then no longer be applied to the skeletons, thus creating significant nomenclatorial