The channel-billed toucan (Ramphastos vitellinus) is a near-passerine bird in the family Ramphastidae found on the Caribbean island of Trinidad and in tropical South America as far south as southern Brazil and central Bolivia. Taxonomy and systematics Subspecies Three subspecies are recognized: Yellow-ridged toucan (R. v. culminatus) - (Gould, 1833): Originally described as a separate species. Found in upper Amazonia from western Venezuela to northern Bolivia R. v. vitellinus - Lichtenstein, 1823: Found in Venezuela, the Guianas, northern Brazil and Trinidad Ariel toucan (R. v. ariel) - Vigors, 1826: Originally described as a separate species. Found in central and eastern Brazil south of the Amazon River These subspecies were previously considered separate species, but all three, along with the citron-throated toucan, will interbreed freely wherever they meet. However, the subspecies R. v. ariel is closer to R. v. culminatus than to the nominate, and are by some already considered close to distinct species status. As R. v. ariel was described before R. v. culminatus, if separated they would become Ramphastos ariel ariel and R. a. culminatus. There also exists an isolated population in eastern Brazil. It looks very similar to, and has traditionally been considered part of, R. v. ariel, but molecular analysis suggests that it has been isolated for a long time and is a yet-undescribed separate subspecies or possibly even species (Weckstein, 2005). Description Like other toucans, the channel-billed is brightly marked and has a huge bill. It is typically long with a 9–14 cm (3½-5½ in) bill. It weighs Nominate race (R. v. vitellinus): Its upperparts, belly, tail and most of the bill are black, and the uppertail and undertail coverts are red. The bare eye-patch and bill base are blue, the throat is white, most of the central breast is yellow-orange fading to white laterally and the lower breast sharply contrasts with a broad transverse red band. The iris is dark brownish. It is found in the north-eastern part of this species' range. Race culminatus: It resembles the nominate, but has a yellow base of the upper mandible and ridge to its bill, orange-yellow uppertail coverts and the throat and breast are white (occasionally tinged yellow), with just a narrow red band separating the latter from the black belly. It occurs in the eastern and south-central part of this species' range. It is very similar to, and easily confused with, Cuvier's toucan (Ramphastos tucanus cuvieri). Race