Archaeornithes now thought to represent a single species, "Archaeopteryx lithographica", the "Archaeornis" being the Berlin specimen of "Archaeopteryx". While rarely used by palaenthologists today, the term was revived by the ornithologists Livezey and Zusi in 2007, for a group comprising Archaeopterygidae and the Confuciusornithidae. Archaeornithes The Archaeornithes, classically Archæornithes, is an extinct group of the first primitive, reptile-like birds. It is an evolutionary grade of transitional fossils, the primitive birds halfway between non avian dinosaur ancestors and the derived modern birds (avian dinosaur). Fossils of early birds were poorly known until the late 20th century. Of those known, all fell into
Specimens of Archaeopteryx other "Archaeopteryx" specimens. The left wing preserves the better plumage and shows flight feathers firmly connected to the arms. Though the wings overlap each other enough that assigning feather attachment points to individual bone regions is not possible, it does appear, consistent with other specimens and modern relatives, that the long primary feathers are attached to the second manual digit. The feathers of the right wing are considerably more damaged; so many feathers are missing that only a few can be definitively linked to the ulna, designating them as secondary remiges. One small feather is isolated next to the right