The yellow-throated toucan (Ramphastos ambiguus) is a Near Threatened species of bird in the family Ramphastidae, the toucans, toucanets, and aracaris. It is found from Honduras south into northern South America and beyond to Peru. Taxonomy and systematics Three subspecies of yellow-throated toucan are recognized: "Chestnut-mandibled" toucan, R. a. swainsonii - (Gould, 1833) "Black-mandibled" toucan (in part), the nominate R. a. ambiguus - Swainson, 1823 "Black-mandibled" toucan (in part), R. a. abbreviatus - Cabanis, 1862 All three subspecies were originally described as separate species. R. a. abbreviatus was relatively early reassigned as a subspecies of R. a. ambiguus. Subspecies R. a. swainsonii differs from ambiguus by 1.35% in mitochondrial DNA which led to its treatment as a species by major taxonomies until about 2010. Description The yellow-throated toucan is long and weighs . The three subspecies differ little in their dimensions, though females' bills are shorter than males' in all three. Bill lengths vary between in males and in females. Other measurements differ little by sex. Their wing chord is , their tail length is , and their tarsus is long. The yellow-throated toucan's subspecies have essentially the same plumage. They are mostly black, with a maroon tint to the hindneck and upper back and white uppertail coverts. Their face, throat, and upper breast are bright yellow with white and crimson bands below the breast. Their vent and undertail coverts are bright red. The bare skin around their eye does differ: sky blue in the nominate R. a. ambiguus, yellow green in R. a. abbreviatus, and varying between yellow and bright green in R. a. swainsonii. The three subspecies' bills differ as well. All have a mostly yellow maxilla with a greenish yellow stripe on the culmen and a thin black line at the base. The nominate and R. a. abbreviatus have black mandibles; R. a. swainsonii[{apostrophe]}} is maroon to reddish chestnut brown. Distribution and habitat The subspecies of yellow-throated toucan are found thus: R. a. swainsonii, from southeastern Honduras through Nicaragua, Costa Rica, Panama, and western Colombia to southwestern Ecuador R. a. ambiguus, from southwestern Colombia on the eastern slope of the Andes to south-central Peru R. a. abbreviatus, northeastern Colombia and northwestern and northern Venezuela The "chestnut mandibled" R. a. swainsonii primarily inhabits lowland evergreen primary forest and also occurs in gallery forest, older secondary forest, and well-treed parks and gardens. It shuns dry forest and large open