Chestnut-throated Seedeater

The chestnut-throated seedeater is 10 to 10.5 cm (3.9 to 4.1 in) long; two males weighed 8.4 and 10.9 g (0.30 and 0.38 oz). It has a short, thick bill with a rounded culmen. The species is sexually dimorphic. Adult males have a medium gray head with deep chestnut bases on the crown feathers that show as the feathers wear. Their upperparts are mostly grayish with a slightly browner hindneck and lower back and dusky streaks on the crown and mantle. Their rump is white and their uppertail coverts gray. Their tail is mostly blackish with grayish feather edges and a small amount of white on the feathers' bases. Their wings are blackish with grayish edges on the coverts and tertials that sometimes show as two faint wing bars. The wings have white bases on the primaries that show as a patch on the closed wing. Their throat and upper breast are dark chestnut with tiny white spots at the base of the bill and the rest of their underparts are whitish. "Tumaco" seedeaters have mostly chestnut underparts with a whitish belly center. Females have a warm brown head and upperparts with darker streaks on the crown, nape, and mantle. Their wings are blackish with warm brown edges on the coverts and tertials and the same white primary patch as males. Their tail is blackish with warm brown feather edges. Their throat is white with a buffy band on the breast that continues along the flanks. …

The chestnut-throated seedeater is found in southwestern Colombia on Gorgona Island off Cauca Department and Tumaco Island off Nariño Department. Its range continues in the coastal lowlands for the lengths of Ecuador and Peru into far northern Chile's Arica y Parinacota Region. In Ecuador it reaches the Andean foothills in El Oro and Loja provinces and in Peru is also inland in the valley of the Marañón River. It inhabits grassy and shrubby landscapes including dry grasslands, agricultural areas, desert oases, and settled areas. In elevation in Ecuador it is mostly below 500 m (1,600 ft) but locally reaches 1,400 m (4,600 ft). It reaches 700 m (2,300 ft) in Peru.

The chestnut-throated seedeater feeds primarily on grass seeds. It usually feeds while clinging to stems but sometimes on the ground. Outside the breeding season it often forages in flocks that include other seed-eating species.