The White-eared titi (Plecturocebus donacophilus) is a diurnal monkey that inhabits low-level branches near the ground in the rainforests of Bolivia and Brazil and moves quadrupedally. Body length is about 30 cm and body mass is 0.9–1 kg, with males tending to be slightly larger. Groups are pair-based of 2–7 individuals and are monogamous; each group holds a territory which it advertises with song. Diet is mainly frugivorous, with fruit making up over 70% of intake; they also eat leaves, seeds, and insects. Reproduction is seasonal; gestation lasts about 18 weeks and typically produces a single offspring. Sexual maturity is reached at about 2 years, and captive lifespan is about 25 years. Although affected by forest destruction, its current conservation status is of Least Concern.