Genus: Acristatherium HU, MENG, LI & WANG, 2010 (published in 2009)
Etymology: Greek, acrista, "crestless," in reference to the absence of a sagittal crest on the skull, and Greek, therion, "beast."

Species: yanensis HU, MENG, LI & WANG, 2010 (published in 2009)
Etymology: 'Yan' representing Yanzigou, Laioning Province, China, the name of the locality.

Holotype: IVPP V15004

Locality: Yanzigou, Shangyuan, Beipiao, Laioning Province, China.

Horizon: Lujiatum Bed, Yixian Formation.

Horizon: Yixan Formation.

Biostratigraphy:

Age: Lower Aptian Stage, Middle Gallic Subepoch, Upper Early Cretaceous Epoch, Early Cretaceous.

Material: Skull and fragmentary dentary.