Sugar glider

The flying squirrel is a non-hybridized creature native to the forrests in the Earth Kingdom. It is a small creature, capable of gliding certain distances.

History
While trying to find Korra, Ikki came across one of these little forrest creatures, while it was eating a berry of sorts. Startled, it dropped the berry and quickly ran up a tree, before gliding away. Ikki, flying with her wingsuit, tried to give him his berry back, but it flew away, leaving her distracted and she subsequently crashed into a tree. The squirrel landed on her head again, after his berry had been crushed on her cheek and licked off the remains. When Ikki was captured, it got taken with her to the soldiers' post, where it patiently waited of her rescue. After Jinora and Meelo had knocked out the soldiers, the squirrel jumped on Ikki's head again while she left.

Anatomy
The flying squirrel is a small creature, roughly the size of a mouse. It is primarily gray, being a bit darker on its back than on its belly. It also has a dark stripe both running down its spine, as well as a similar stripe marking the front and sides of its wings. The tail of the animal is thicker than the ones you would find on a rat, but not as thick as a regular squirrel.

Behavior
The flying squirrel is a shy animal, willing to drop its food when trouble arises. However, it is also quite a trusting creature, landing on Ikki after she offered one his food back. Its diet consists of, among other things, berries.

Connection
Much like a real-world flying squirrel, the wings of the animal can fold out to try and extend its jumping range. it should be noted that the animal in the show is smaller, exceot for the eyes, which appear to be relatively a lot larger.