Gas giant
The smallest known extrasolar planet that is likely a "gas planet" is Kepler-138d, which has the same mass as Earth but is 60% larger and therefore has a density that indicates a thick gas envelope.
Least pygmy squirrel
The least pygmy squirrel ("Exilisciurus exilis"), also known as the plain pygmy squirrel, is a species of rodent in the family Sciuridae. This plain olive-brown squirrel is endemic to forest in Borneo and the Banggi Island. It is among the smallest squirrels in the world.