Dabeigou Formation
The Dabeigou Formation is a palaeontological formation located in China. It dates from the mid Valanginian to Hauterivian age of the Cretaceous period. Approximately 135-130 ma.
Fossils include the confuciusornithiform bird Eoconfuciusornis. As of 2016 this is the oldest bird with a toothless beak known, but it belongs to a very ancestral avian lineage not closely related to living birds.
