The Phelps’ Brush-Finch is part of the Arremon genus, which has a variety of species that distribute through all South America, a few of which occur in Costa Rica. They are small birds that hop in the ground and forage by snatching worms and insects from their hides. Its back and wings are olive in coloration, with gray flanks that join with the supercilliary. It has black cheeks and a black line above the supercilliary, with a gray line that goes through the center of the head, and those features give it a striped look. It has a white throat and chest. Their eyes are reddish-brown.