What is "protopithecus"

Protopithecus is an extinct genus of large New World monkey that lived during the Pleistocene. Fossils have been found in the Toca da Boa Vista cave of Brazil, as well as other locales in the country.

At an estimated weight of 22.6 kg (50 lb), it was the largest New World monkey known to exist. With slightly longer arms than legs, Protopithecus resembled spider monkeys, but its limb bones were nearly twice as thick. Its head was more similar to a howler monkey's, which has a lower jaw that juts forward to accommodate an apple-size vocal sac. As such, Protopithecus may have been able to howl just like them.

Although closely related, howler and spider monkeys split from their common ancestor long before Protopithecus evolved. This means that the distinctive features of these modern monkeys have evolved more than once.