Stephen Nash's titi as on the underside of the species' limbs. It is 28 inches long, although 17 inches is taken up by the titi's tail. Stephen Nash's titi Stephen Nash's titi ("Plecturocebus stephennashi"), also known as just Nash's titi or Stephen Nash's monkey, is a species of titi, a type of New World monkey, endemic to the eastern bank of the Purus River in Brazil. It was discovered by Marc van Roosmalen in 2001 when local fishermen brought specimens to his breeding center. It was described in 2002. It was named in honor of Stephen D. Nash, an illustrator for Conservation International,
White-eared titi be quite tolerant of habitat disturbance. In Bolivia, the white-eared titi is found in the upper parts of the Mamoré, Grande, and San Miguel river basins, east of the Manique River in Beni and in the forests surrounding the city of Santa Cruz de la Sierra. Its range extends north to southern Rondônia in Brazil. The white-eared titi is considered to be of least concern on the International Union for Conservation of Nature (IUCN) Red List. The species is not considered threatened due to its adaptability and abundance over a relatively wide range, and despite having a decreasing population trend