The golden-headed lion tamarin's name describes its striking appearance perfectly. The thick, long golden to orange mane around its face is indeed reminiscent of a male lion's mane (3). When in danger or defending its territory, this tamarin raises its fantastic mane and fluffs up its fur to give it the appearance of being bigger than it really is, whilst flicking its tongue at the intruder to scare them away (5). Females and males are very similar in appearance, as are the young, but unlike most other primates, it is the adult female that is usually larger than the adult male (6). The body is predominantly shiny and black, with golden to orange limbs and paws, and a black and golden coloured, long tail (7). Its fore and hind limbs are similar in size, allowing it to move quadrupedally through the forest (6). Their fingers are long and dextrous and, like all callitrichids, the nails have evolved into claws on all but the big toe, which has a flattened nail, allowing them to climb in a squirrel-like fashion through the trees (2) (3) (5).