About Euphonia laniirostris d'Orbigny & Lafresnaye, 1837
The thick-billed euphonia, with the scientific name Euphonia laniirostris, is a bird species that belongs to the family Fringillidae; it was previously classified in the family Thraupidae. Adult thick-billed euphonias reach a length of 10 cm (3.9 in). Males of this species have entirely yellow underparts from the throat to the vent, with only a small terminal white patch on the undertail. Their upperparts are dark blue-black, except for a yellow patch on the crown that extends from the bill over the head to just past the eye. Females, like females of many other euphonia species, are dull olive on their upperparts and yellow on their underparts. This species occurs in Bolivia, Brazil, Colombia, Costa Rica, Ecuador, Panama, Peru, and Venezuela. Its natural habitats are subtropical or tropical dry forests, subtropical or tropical moist lowland forests, and heavily degraded former forest.