Planetetherium

Planetetherium is an extinct genus of herbivorous gliding mammal endemic to North America during the Paleogene living from 56.8 to 55.4 mya, existing for approximately.

Fossils have been discovered in strata formed from ancient cypress forests, suggesting that this was the animal's preferred habitat.

Morphology
Plantetherium measured around 25 cm in length, and its skeleton closely resembled that of its modern relatives. Its teeth already included the comb-like structure distinctive to modern colugos. There is no direct evidence that Planetetherium had the membrane of skin that allows modern colugos to glide, but its bodily proportions suggests that this was likely the case.