As the name suggests, this seed-finch has a truly massive bill – much larger than any seedeater. Male is all black with a small white wing patch. Bill is pale whitish or silvery. Female is brown with a dark bill. Very similar to Great-billed Seed-Finch, which is slightly larger; thankfully there is limited range overlap. Occurs in lowlands, primarily in scrubby or grassy fields and marshes. Uncommon.