Small, chunky finch with thick gray bill. Male deep blue-black, female brown, both sexes with white underwings. Mostly found in pairs in the understory of spiny bamboo forest. Song a fast musical warble of four or six notes “pee PEEu pee PEEu peePEEuu.” Similar to Blue-black Grassquit, which is smaller with a more conical bill; also to Amazonian Grosbeak, which is larger with a bulkier bill. Little known, endemic to the southern lowlands of Venezuela.