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 1998, Vieser 1988). The Eichstätt specimen of "Archaeopteryx" is represented by an almost-complete skeleton visible on both slab and counter-slab, though the majority of the skeleton is on the main (overlying) slab. The animal is preserved lying on its right side, as in the Berlin specimen. The specimen is in almost complete articulation with many items in their original positions. The vertebral column, which had become strongly recurved in death, enabled the animal's head to lie above the pelvis in near-perfect preservation. This excellently-preserved skull is one of the most notable features of this specimen. The majority of the Eichstätt