Taken just outside Belo Horizonte, Minas Gerais in 2006.
From what I understand, in English their name is “black tufted marmoset” or “black-tufted tamarin”.
In Brazil tiny little monkeys like these are all referred to as a mico (which made the name of Pocahontas’ raccoon - Meeko - really confusing for me as a kid).
This specific kind is known as a mico estrela (star mico, due to the little star on its forehead).
When I was young these guys would come onto our porch and take our food
There was one that would come up to my classroom and wait for us to share our lunch (his favourite was ham-flavoured Fandangos xD)
My mom’s friend lives in an area where she has to keep the windows locked at all times otherwise they get in and tear up the kitchen looking for snacks. Kinda like the scene from Jumanji with the monkeys in the kitchen.