Colugos are arboreal gliding mammals found in South-east Asia. There are just two species each in its own genus, which makes up the entire family Cynocephalidae and order Dermoptera. Though they are the most capable of all mammal gliders, they cannot actually fly. They are also known as cobegos or flying lemurs.
Colugos are fairly large for a tree-dwelling mammal. They are about 13.78 to 15.75 in (35 to 40 cm) long and 2.2 to 4.41 lbs (1 or 2 kg) in weight. They are comparable to a medium-sized possum or a very large squirrel. They have moderately long, slender limbs of equal length front and rear. They have a medium-length tail, and a relatively light build. The head is small, with large, front-focused eyes for excellent binocular vision. They have small rounded ears.
Their most distinctive feature, however, is the membrane of skin. It extends between their limbs and gives them the ability to glide long distances between trees. Of all the gliding mammals, the colugos have the most extensive adaptation to flight. Their gliding membrane is as large as is geometrically possible. It runs from the shoulder blades to the forepaw, from the tip of the rear-most finger to the tip of the toes, and from the hind legs to the tip of the tail. Even the spaces between the fingers and toes are webbed to increase the total surface area.
They are surprisingly clumsy climbers. Lacking opposable thumbs and not being especially strong, they proceed upwards in a series of slow hops. They grip onto the bark of trees with their small, sharp claws. They are as comfortable hanging underneath a branch as sitting on top of it. In the air they can glide as far as 76.55 yards (70 m) from one tree to another with minimal loss of height.
Colugos are shy, nocturnal, and restricted to the tropical rainforests of Southeast Asia. Remarkably little is known about their habits. They are certainly herbivores. They are thought to eat mostly leaves, shoots, flowers and sap, and probably fruit as well. They have well-developed stomachs capable of extracting nutriment from leaves.