Species: inexpectus XU, TANG & WANG, 1999
Etymology: Inexpectus: referring to the surprising features in this animal.
Holotype: IVPP V11559
Locality: Sihetun, Shangyuan, near Beipiao City, Liaoning Province, China.
Horizon: Horizon 1, Lower part of the Yixian Formation, Jehol Group.
Biostratigraphy: Psittacosaurus Fauna, Confuciusornis Avifauna.
Age: Valanginian Stage, Upper Neocomian Subepoch, Early Early Cretaceous Epoch, Early Cretaceous.
Material: Fragmentary dentary, splanchocranium, neurocranium, and palate,
and fragmentary skeleton with ‘feather’ integument?
Note: XU, CHENG, WANG & CHANG, 2003 report newly found pelvis and pygostyle
tail with feather impressions from the type specimen.
Note: Has a furcula.