Amazon Dwarf Squirrel

The Amazon dwarf squirrel (Microsciurus flaviventer) is a chipmunk-sized tree squirrel native to South America. == Description == As its name suggests, the Amazon dwarf squirrel is relatively small, with a head-body length of 12 to 16 cm (4.7 to 6.3 in) and a tail 8 to 16 cm (3.1 to 6.3 in) long. Adults weigh between 86 and 132 g (3.0 and 4.7 oz), with males being slightly larger than females. The fur varies from reddish to dull brown, fading gradually to yellow or greyish on the underparts. There is a distinctive patch of pale yellow fur behind the ears, while the tail has faint yellowish bands and white frosting. The limbs are unusually long for tree squirrels. In the forelimbs, the humerus and radius are of equal length, an adaptation thought to increase the squirrel's ability to climb large trees, compensating for a lack of shoulder mobility. The longer hindlimbs allow for stronger muscles, so that the squirrel can leap over larger gaps, relative to its size, than more typically sized squirrels can. == Distribution and habitat == The squirrels are found in the upper Amazon Basin, broadly west of the Purus and Rio Negro rivers, in Brazil…