The Pygmy tarsier is Indonesia’s smallest primate species. It was though to have become extinct during the early 20th century. However, in 2000, one was accidentally killed by Indonesian scientists while trapping rats. The first of this species seen at large since the 1920s were discovered by researchers from Texas A&M University in Lore Lindu National Park on Mount Rore Katimbo in August 2008. This animal’s coat is longer and more curly than that of other tarsiers, perhaps as an adaptation to its cold damp environment. Its coat is very soft, ranging in color from buff to grayish brown or dark brown.
Pygmy tarsiers come from Central Sulawesi, Indonesia. They inhabit montane cloud forests in the central Sulawesi Mountains at altitudes from 1800 to 2200 m. They often inhabit the lower canopy among trunks of saplings, and the forest floor.
One group only of Pygmy tarsiers in the wild has been recorded: a group 3 adults: 1 female and 2 males, which for other tarsier species is unusual. Tarsiers are crepuscular or nocturnal and are mainly arboreal. During the day they spend most of their time amongst dense vegetation sleeping on vertical branches or perhaps in hollow trees. When disturbed during resting they may move up or down the branch facing towards the threat, their mouth open, and their teeth bared. When they are waking, they continuously crinkle or furl their ears. These animals spend much time looking for prey while low down on tree trunks. They do not make nests, but may return to sleep in the same tree. Unlike other tarsiers, the pygmy tarsier does not mark territorial boundaries by means of scent glands. As with all primates, tactile communication between Pygmy tarsier mothers and offspring, as well as between mates, is important.
As they are infrequently seen and until lately were regarded as a subspecies of spectral tarsiers, not much is known about their mating system. Spectral tarsiers, a member of the same genus and their closest geographic neighbor, are typically monogamous (where one male mates exclusively with one female), though some social groups consistently demonstrate polygyny (one male mating with multiple females). This species has two breeding seasons, the first when the rainy season begins and the other at its end, about 6 months apart. Gestation on average is for 178 days, and there is a single birth. Infants are quite precocial, developing quickly, similar to other young in the genus. They can travel in groups when 23 days old and can hunt alone when 42 days old. Females stay with their parents until they are adults, while males disperse from the natal group while juveniles.
The biggest threat to this species is habitat loss and degradation. Hunting and fires set by humans are also threats, and, together with logging, are probably going to continue in the future. Transmigration and local clearance are other threats.
The IUCN Red List and other sources do not provide the Pygmy tarsier total population size. Today this species’ numbers are decreasing and it is classified as Data Deficient (DD) on the IUCN Red List.
As insectivores, Pygmy tarsiers have an important role in their environment as regards control of the insect community and having an impact on local food webs. They are also preyed upon by diurnal raptors.