The aye-aye is a long-fingered lemur, a 'strepsirrhine' primate native to Madagascar with rodent-like teeth that perpetually grow and a special thin middle finger. It is the world's largest nocturnal primate.

The aye-aye is the only extant member of the genus 'Daubentonia' and family 'Daubentoniidae'. It is currently classified as 'Endangered' by the IUCN (International Union for Conservation of Nature).

The aye-aye was thought to be extinct in 1933 but was rediscovered in 1957. Recent research shows the aye-aye is more widespread than was previously thought, but its conservation status was changed to 'Endangered' in 2014 (from 'Near Threatened' in 2008) and reassessed as 'Endangered' on the 7th of May 2018.

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