Genus: Hyphalosaurus GAO, TANG & WANG, 1999

Species: baitaigouensis JI, JI, CHENG, YOU, LÜ & YUAN, 2004
Etymology:

Locality: Baitaigou village, northwest of the Yizhou town, Yixian County, Liaoning Province, China.

Horizon: Yixian Formation, Jehol Group.

Biostratigraphy: Psittacosaurus Fauna, Confuciusornis Avifauna.

Age: Valanginian Stage, Upper Neocomian Subepoch, Early Early Cretaceous Epoch, Early Cretaceous.

Referred material:

JI, WU & CHENG, 2010

CAGS-IB-06131: Nearly complete specimen.

Note: Has 18 embryos in the body cavity.