It had been regarded as synonymous with the shock-headed capuchin (C. cuscinus), which was then considered a subspecies of Humboldt's white-fronted capuchin, but it was classified as a separate species by Mittermeier and Rylands based on genetic studies by Boubli.

[2][3][4] The Marañón white-fronted capuchin lives in wet forests of the upper Amazon basin in southern Colombia, eastern Ecuador, northeastern Peru and likely eastern Brazil.

[2][3] Males have a head and body length of about 43 cm (17 in) with a tail length of about 47 cm (19 in).

[2] Females have a head and body length about 37 cm (15 in) with a tail length of about 45 cm (18 in).

[2] Marañón white-fronted capuchins sometimes formed mixed groups with the Ecuadorian squirrel monkey.