Horsfield's tarsier

Horsfield's tarsier, also called the western tarsier, is the only species in the tarsier genus Cephalopachus and was named for the American naturalist Thomas Horsfield. It lives on Borneo, Sumatra and nearby islands, in primary and secondary forest as well as along coasts and at the edges of plantations. Entirely nocturnal, it sleeps alone by day in a tangle of vines and spends part of each night foraging in the understory, where it takes mainly arthropods such as beetles, grasshoppers and cicadas, along with small vertebrates including bats, frogs and even venomous snakes. Four subspecies are recognised, though the taxonomy is in doubt and a revision based on systematic field surveys is overdue. It is listed as vulnerable on the IUCN Red List and in CITES Appendix II, and it is threatened by forest conversion, oil palm plantations, fire, logging and the illegal pet trade.