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Archaeornithura

Archaeornithura is an extinct genus of ornithuromorphs from the early Cretaceous period. It is known from two fossil specimens of a single species, Archaeornithura meemannae. The specimens have been dated to the Hauterivian age, 130.7 million years ago, making A. meemannae the oldest known ornithuromorph, the lineage that gave rise to modern birds, and contains all living birds as well as many of their extinct relatives.