Teinolophos is a poorly-understood Mesozoic mammals, currently known only from a few partial lower-jaw bones. several jaw features demonstrate that Teinolophos was a monotreme - sometime called egg-laying mammals. The platypus and the echidnas(or spiny anteaters) are the only living monotremes and are found only in Australia. Teinolophos was originally thought to be an early monotreme, only distantly related to the platypus and echidnas. However, work published in 2008 showed that it possessed several features unique to platypuses, but not echidnas.