Archaeoindris fontoynontii was a giant lemur endemic to, of course, Madagascar. Known as the “gorilla lemur” due to its size, it was also the largest member of a family called “sloth lemurs” due to their similarity to ground sloths. Remains are scarce, but it is estimated they were around the size of an adult male gorilla and weighed about 538 pounds. It’s skeleton suggest that was well-suited for both climbing and walking.
Archaeoindris probably went extinct only around 350 BC, with the arrival of humans on Madagascar.
(Side note: I try not to make the eyes too detailed to keep a thread of same style going for this series, but it’s too hard to draw a lemur without pupils... without it being absolutely terrifying. So you’ll have to forgive the slight style shift for this one.)