[3] A 2015 genetic study by Lynch Alfaro, et al revealed that Collins' squirrel monkey, S. collinsi, from northeastern Brazil, which had also been considered a subspecies of S. sciureus, should also be treated as a separate species.

[5] The Guianan squirrel monkey has a pink face, black muzzle and white arches over the eyes.

[6] The fur on its back can vary in color among gray, olive or orange, but the belly is white and the arms are yellow-orange.

[5] The Guianan squirrel monkey's diet includes insects, seeds, fruit, young leaves, flowers, gum, shoots, nectar, spiders, lizards and bird eggs.

[5] Gestation period is about 5 months, and all infants within a group are typically born within one week of each other during January or February.