Purple-throated Euphonia
Euphonia chlorotica
The purple-throated euphonia is 9 to 10 cm (3.5 to 3.9 in) long and weighs about 8 to 14 g (0.28 to 0.49 oz). The species is sexually dimorphic. Adult males of the nominate subspecies E. c. chlorotica have a bright yellow forehead and forecrown; the color extends to the rear of the eye. The rest of their head and their upperparts are glossy blue-black that in good light has a purplish tinge. The upper side of their tail is blackish and the underside duller with white on the inner webs of the outer two or three pairs of feathers. Voice: The purple-throated euphonia's song is "a jumbled series of squeaks, harsh notes and whistles" that is infrequently heard. A typical call is "a high, clear, whistled teee, deee" that is often lengthened to three or four notes as "teee, deee, deee"; occasionally it makes only a single "teee". The notes are on a single pitch.
ID text from Wikipedia, CC BY-SA 4.0
Thick-billed Euphonia
Euphonia laniirostris
The thick-billed euphonia is about 10 cm (3.9 in) long and weighs 13 to 16.5 g (0.46 to 0.58 oz). It is a small euphonia with one of the thicker bills of all euphonias, though it is not dramatically larger than the others'. The species is sexually dimorphic. Adult males of the nominate subspecies E. l. laniirostris have a bright yellow forehead; the patch extends slightly past the eye. The rest of their crown and their face, nape, and upperparts are glossy blue-black. Their upperwing coverts and flight feathers are dusky with a dark blue tinge. Voice: The thick-billed euphonia is rather vocal and a good mimic of other birds' vocalizations. Its song is "highly variable, a choppy series of call notes mixed with whistles, warbles, and piercing notes". Another description is "a long rambling series of original notes and mimicked notes of other birds". Its calls include " loud, sharp, whistled preet!
ID text from Wikipedia, CC BY-SA 4.0

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Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: Purple-throated Euphonia and Thick-billed Euphonia.