The spectral tarsier (Tarsius tarsier) is a member of the tarsier family and living on the island of Sulawesi, Indonesia, and is also referred to as 'Sulawesi tarsier'. It is about 25 centimetres long and weighs 94-154 grams. They sleep in hollow trees, palm trees or thick vines. Spectral tarsiers are not very social animals, they encounter each other only once in a while during the night when they feed on insects. During the day they sleep most of the time and socially interact only a short time of the day.