Arguably the most charismatic of the tamarins, the emperor tamarin (Saguinus imperator) is a small primate named for its characteristic long white moustache, which is thought to bear a resemblance to the moustache of Emperor Wilhelm II of Germany. The distinctive moustache of the emperor tamarin forms the basis of identification for the two recognised subspecies: the bearded emperor tamarin (Saguinus imperator subgrisescens), which has a full white beard, and the black-chinned emperor tamarin (Saguinus imperator imperator), in which the white hair below the mouth is absent. The emperor tamarin belongs to the Callitrichidae family, a group of New World monkeys containing both tamarins and marmosets. In general, all species in the family have fine, silky coats. The emperor tamarin is grey on the body and silvery-brown to black on the crown, with a dull gold or reddish-orange tail. It is typically white on the underparts. The male and female are very similar in appearance, while juvenile emperor tamarins are considerably smaller than the adults and possess shorter moustaches. Vocalisations of the emperor tamarin include hisses, trills and long chirping calls that are mostly used for threat and dominance displays within its social group.