朝阳市
"Pengornis" is known from a single adult fossil, described by Zhou et al. in 2008. This holotype is in the collection of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing China. Its accession number is IVPP V15336. It was collected from the Jiufotang Formation, at Dapingfang, Chaoyang, Liaoning China. A second, juvenile specimen was described by Hu, Zhou, and O'Connor in 2014.