Jeholodens is an extinct genus of primitive mammal belonging to the order Eutriconodonta, and which lived in present-day China during the Middle Cretaceous about 125 million years ago.
This specimen (the holotype) consists of a virtually complete articulated skull and skeleton, it shared its corporal characteristics with most other Mesozoic mammals; it was a long-tailed, nocturnal tetrapod (with prehensile fingers and toes) which hunted insects, its food, during the night.
It is notable for its relatively derived forelimb morphology, having shoulder blades and other pectoral girdle elements comparable to those of modern therians like opossums.
By contrast, however, the hindlimbs retained primitive characters, suggesting a sprawling stance.
[1][2] Recent studies show that it was specialised to an arboreal lifestyle, possessing prehensile hands.