Maranhão Red-handed Howler (Alouatta Ululata)

The Maranhão red-handed howler is an endangered species of howler monkey endemic to forests in the northeastern Brazilian states of Ceará, Maranhão and Piauí. It was previously thought to be a subspecies of the red-handed howler, but unlike that species, the Maranhão red-handed howler is strongly sexually dichromatic.