Characterization: Small species measuring about 11.5cm in length. The male is shiny black; females and young individuals are olive-brown on their upper parts, brownish-yellow on the bottom, with dark striated chests and sides.

Distribution: All South American countries.

Habitat: All kinds of open landscapes, such as high grasslands, agricultural areas, around housing, abandoned plots of land in cities, etc.

Habits: A diurnal species, this bird live in pairs during the breeding season; however, in periods other than this, it gathers in flocks that may add up to tens of individuals. In these situations, it often mixes with other bird species that feed on seeds.

Diet: Herbivorous, predominantly granivore.

Breeding: This bird lays 1 to 3 in thin, deep-cup-shaped nests built on grasses.

In the UFRA area: The Blue-black Grassquit was frequently seen in the surveys done, having been spotted 57 times. Its distribution is quite broad, being present in the organic sugarcane crops, wetlands with herbaceous plants, wetlands with riparian forests, restored native forests, in mixed forests in regeneration, native forests, in drainage ditches, and in forests and fields in spontaneous regeneration.