Mono Grande

The German naturalist Alexander von Humboldt, who travelled in South America during early 19th century, heard stories from Orinoco about furry human-like creatures called Salvaje ("Wild"), which were rumoured to capture women, build huts and to occasionally eat human flesh.

[2] In 1931, inspired by Loys' ape, three Italians made an expedition to the Mazaruni River in Guyana, but without further evidence than more alleged sightings from the residents.

Bengt Sjögren writes (1980) that: "They returned home with a couple of eyewitness-reports, that give the impression that the interviewed tried to make fun of the [sic?]

The American scientist Philip Herschkowitz, who traveled in the same areas as de Loys, concluded that the story was a myth whose origin was the spider monkey, Ateles belzebuth.

The Swedish author Rolf Blomberg speculates (1966) that rumours of hidden monsters in the Amazon basin might have been inspired by Arthur Conan Doyle's book The Lost World (1912) combined with exaggerated reports of sightings of unusually large spider monkeys (Sjögren, 1980), and Bengt Sjögren (1962) remarked: "For critically educated zoologists is of course all this 'ape mystery' just a good joke".