The Aye-aye (Daubentonia madagascariensis) is a lemur native to Madagascar that combines rodent-like teeth with a long, thin middle finger to fill the same ecological niche of a woodpecker. It is the world's largest nocturnal primate, and is characterized by its unique method of finding food; it taps on trees to find grubs, then gnaws holes in the wood and inserts its elongated middle finger to pull the grubs out.
Daubentonia is the only genus in the family Daubentoniidae and infraorder Chiromyiformes. The Aye-aye is the only extant member of the genus (although it is currently an endangered species); a second species (Daubentonia robusta) was exterminated over the last few centuries.
Ayeaye on Wikipedia
Ayeaye on BBC Science & Nature