Tarsier, a small mammal found in the jungles of Borneo, Sumatra, Celebes, the Philippines, and other islands nearby. The tarsier is a primate (a member of the order of mammals to which humans and the apes belong) and is related to the lemurs. It is noted for its large, round eyes. There are three species of tarsiers. The tarsier is named for its unusually long tarsal (ankle) bones.

The tarsier's body ranges in length from 3 to 6 inches (7.5 to 15 cm) and its tail is 5 1/2 to 10 1/2 inches (14 to 27 cm) long. The body is covered by wavy brownish-gray fur, but the tail is bare except for a few short hairs at the tip. The fingers and toes are tipped with rounded, fleshy pads that enable the tarsier to climb almost any surface. Tarsiers are active only at night and spend most of their time in trees. They eat mainly insects and lizards. The Philippine and Bornean tarsiers are threatened with extinction due to loss of their forest habitats.

The Philippine tarsier is Tarsius syrichta of the family Tarsiidae; the Bornean, or western, T. bancanus; and the Sulawesi, or eastern, T. spectrum.