Rocky the Flying Squirrel was created in 1959.
Rocky
It is not an idiom - it is a line from an old television cartoon called Rocky and Bullwinkle. Rocky was a flying squirrel. (Bullwinkle was a moose).
Smoky Flying Squirrel was created in 1873.
Bartel's Flying Squirrel was created in 1939.
Kashmir Flying Squirrel was created in 1837.
Siberian Flying Squirrel was created in 1758.
Arrow Flying Squirrel was created in 1766.
Yes
Chinese Giant Flying Squirrel was created in 1872.
Spotted Giant Flying Squirrel was created in 1840.
Indian Giant Flying Squirrel was created in 1839.
Groove-toothed Flying Squirrel was created in 1867.