An extinct mammal, with no modern relatives, that lived in the early Cretaceous (about 124.6 Ma ago). A nearly complete fossil skeleton, found in the Yixian formation in Liaoning, China, was reported in 2006 (Li, G. and Luo, Z.-X. ‘A Cretaceous symmetrodont therian with some monotreme-like postcranial features’, Nature, 439, 195–200). Akidolestes was most closely related to Theria, but displayed some characteristics of Monotremata, including cervical ribs, and the structure of its pubis and hind limbs.
Subjects: Zoology and Animal Sciences.