Homunculus patagonicus

Homunculus patagonicus is an extinct New World monkey of the Miocene known from the Santa Cruz Formation in the far south of Argentina, and the type species of the genus Homunculus. It lived at a latitude of about 55 degrees south, which makes its genus the southernmost non-human primate ever recorded. Florentino Ameghino described it in 1891 from a partial skull found near the Río Gallegos, a specimen later lost and replaced in 2008 by a neotype, and a genus-level revision that year found several other names, among them Anthropops, Pitheculus and Stilotherium, to be junior synonyms. Body mass estimates range from 1.4 to 5.9 kilograms, with a 2025 study giving about 2 kilograms, comparable to a titi or saki monkey. It was probably a diurnal, arboreal climber that ate fruit, leaves and seeds, in a warm, humid landscape of open savanna and forest. Some studies place it in Pitheciidae and others outside the modern groups.