Scrub Euphonia
Euphonia affinis
The scrub euphonia is about 10 cm (3.9 in) long. It weighs 8.5 to 12.8 g (0.30 to 0.45 oz). It has a short stubby bill. The species is sexually dimorphic. Adult males of the nominate subspecies have a small yellow forecrown; the color extends just to the eye. The rest of their head and nape are glossy blue-black with a purplish sheen. Their upperparts are glossy blue-black. Their tail is mostly blackish with white inner webs on the outer two pairs of feathers. Their upperwing coverts and flight feathers are blackish with some dark blue gloss. Voice: The scrub euphonia's calls include "1–3 pure thin whistles, dee-dee-dee, sometimes followed by 2 or 3 more on same or slightly lower pitch", a "shorter whit-it-it-it", and a "longer wheeee". It sings less than it calls, with "a weak twittering and chirping medley, e.g. wheetidy-titity-witity-titity". Its song and that of the West Mexican euphonia are similar but this species' is slower.
ID text from Wikipedia, CC BY-SA 4.0
Yellow-crowned Euphonia
Euphonia luteicapilla
The yellow-crowned euphonia is about 9 to 10 cm (3.5 to 3.9 in) long and weighs 11.4 to 14.5 g (0.40 to 0.51 oz). It has a short stubby bill. The species is sexually dimorphic. Adult males have a large yellow forecrown and crown; the color extends well past the eye. The rest of their head, nape, and throat are glossy blue-black. Their upperparts, wings, and tail are also glossy blue-black. Their breast, belly, and undertail coverts are bright yellow. Adult females have an olive head, upperparts, wings, and tail with a yellowish tinge on the forehead. Voice: The yellow-crowned euphonia sings "a short, dry sputtering series of notes, e.g. pit ditrééa-twiddledee bee bee" that has also been described as "a short wiry chut-tsip ts’tsew tsiuweer". Its call is "a series of 2–3 clear high whistled notes that may be given at varying speed, ee-bee-bee" or given as a longer series "beebee, peepeepee". It also makes "tsit notes" as a contact and flight call.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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