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,
Red-bellied titi whenever two from the same social group are by each other. The red-bellied titi has a variety of postures and facial expressions that it uses as visual signals. Swaying the entire body, turning the head sideways and lowering the head to face downward are examples of these signals. Observers have seen that these signals are a response to a disturbance or escape tendencies. Arching of the back is a signal that the red-bellied titi uses to warn that they're about to attack. This signal is associated with hostility, after they arch their backs an attack usually follows. Other signals associated