Tambor de Crioula is “a dance with African origins, that is found in Brazil, only in the state of Maranhão. The men make the rhythms by playing rustic “tambores” or drums made of wood and leather while the women, in a circle, sing and dance. The high point of this dance is the belly bump which is the signal for the dancer to be substituted by another in the center of the circle.” – Top Tour.
The belly bump is called a “punga”, for more info on this, go here (in PT)
For more on Afro-Brazilian music and dances, try one of these two research papers. (If you like research papers, try changing the number 256 in the url of the second link above, perhaps to 255, 254, 253, etc. That way, new papers will be shown, although on what topic, I don’t know)