Variegated spider monkey  (Ateles hybridus)

Exceptionally long, spindly limbs have inspired the common name of spider monkeys (Atelidae), together with their long prehensile tail that acts almost like a fifth limb. Indeed, their tails have highly flexible hairless tips with skin grooves that help to grip, an adaptation to the spider monkey's strictly arboreal lifestyle. Spider monkeys also possess narrow and thumbless, hook-like hands, with fingers that are elongate and curved (3). The variegated spider monkey ranges in colouration from a light brown to a rich mahogany on the upper surfaces of its body, limbs and head (2). By contrast, the abdomen, inner sides of the limbs and underside of the tail are a paler, buff colour, and a conspicuous white triangular patch marks the forehead (2). While normally light brown, some individuals have been observed with eyes that are a striking pale blue (2).