Archaeoindris
Though similar to "Palaeopropithecus", "Archaeoindris" was significantly larger and more robust. "Archaeoindris" was one of the largest primates to ever evolve, and was the largest-known strepsirrhine primate, weighing an estimated . It was roughly the size of an adult male gorilla, which was first noted by Lamberton.
Mammal
The earliest known ancestor of primates is "Archicebus achilles" from around 55 million years ago. This tiny primate weighed 20–30 grams (0.7–1.1 ounce) and could fit within a human palm.