Mico differs from Callithrix in dental morphology, genetics and geographic distribution: Callithrix species are distributed in eastern Brazil (mainly the Atlantic Forest), while Mico species are distributed in the Amazon rainforest south of the lower Amazon and Madeira Rivers, though a single species, the black-tailed marmoset, also occurs in the Pantanal and Chaco.

M. argentatus tends to live in smaller home ranges (as small as 10 hectares or less) than other Mico species.

[6] Exudates, such as gum and sap, fruit, nectar and fungus make up the bulk of Mico's diet, but it also eats animal prey such as arthropods, young birds, small lizards and frogs.

They are specialized for exploiting exudates by their elongated, chisel-like lower incisors and a wide jaw gape that allows them to gouge bark of trees that produce gums.

Mico's ability to feed on exudates allows it to survive in areas where fruit is highly seasonal or not readily available.