aye-aye (ĪˈĪˈ) [key], name for an aberrant primate, Daubentonia madagascariensis, related to the lemurs but distinguished by its specialized teeth and fingers. A large nocturnal and arboreal primate, it is found in dense bamboo forests in two isolated regions of Madagascar. The aye-aye is about the size of a house cat. It has silver and black fur with reddish underparts, a long, bushy tail, and a small, round head with large eyes and rounded, naked ears. Its fingers and toes are extremely long and end in claws; the thumb and big toes are opposable. The aye-aye uses its exceedingly slender third finger to dig into bark for wood-boring insect larvae, which it detects by means of its acute hearing. It feeds on larvae, other small animals, eggs, and fruit, as well as on bamboo and sugarcane. Its teeth are adapted for gnawing and it was formerly thought to be a rodent because of its large, chisel-shaped, continuously growing incisors. The aye-aye has no fear of humans and will strike at them if annoyed. It has been the object of superstitious fear. It is now almost extinct. It is classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Primates, family Daubentoniidae.