The Ecuadorian squirrel monkey (Saimiri cassiquiarensis macrodon) is a type of squirrel monkey. It had been considered a subspecies of the Guianan squirrel monkey, Saimiri sciureus, but was elevated to a full species, S. macrodon, based on a 2009 study by Carretero-Pinzón, et al.[1] Based on subsequent genetic research by Jessica Lynch Alfaro, et al it was again reclassified as a subspecies of Humboldt's squirrel monkey.[2][3][4]
The Ecuadorian squirrel monkey lives in the western BrazilianAmazon, as well as southern Colombia, eastern Ecuador and northern and eastern Peru.[5] It lives in humid tropical and subtropical forest, preferring dense forest but able to live in secondary forest and disturbed forest as well.[5] It can live at elevations up to 1,200 m (3,900 ft), but where it has been studied in Ecuador it prefers elevations under 500 m (1,600 ft).[5]
The Ecuadorian squirrel monkey has a head and body length of between 25 and 32 cm (9.8 and 12.6 in) with a tail length between 34 and 44 cm (13 and 17 in).[5] Males weigh between 885 and 1,380 g (31.2 and 48.7 oz) and females weigh between 590 and 1,150 g (21 and 41 oz).[5] Its coloration is similar to that of the Guianan squirrel monkey but its fur is darker.[5]