Chestnut-breasted Chlorophonia
Chlorophonia pyrrhophrys
The chestnut-breasted chlorophonia is a chunky, short-tailed, stubby-billed bird. It is about 12 cm (4.7 in) long and weighs 16 to 18 g (0.56 to 0.63 oz). The species is sexually dimorphic. Adult males have a green forehead and a rich cyanine-blue crown and nape. They have a thin dark red band between them that extends past the eye and a thin pale blue band at the base of the nape. Their lores, face, throat, and upper breast are shiny emerald-green with a thin black line beneath the upper breast. Their mantle, back, and upperwing coverts are bright green and their rump bright yellow. Voice: One description of the chestnut-breasted chlorophonia's song is "a long, rambling tut-tut-tut too-dée...or na-deaár, na-deaár...to-d'leép with variations". Its most common call is "a soft, nasal neck-nuur over and over". It also makes "a nasal, downslurred whistle, teeeur" as a contact call.
ID text from Wikipedia, CC BY-SA 4.0

Yellow-collared Chlorophonia
Chlorophonia flavirostris
The yellow-collared chlorophonia is a chunky, short-tailed, stubby-billed bird. It is about 10 cm (3.9 in) long and weighs about 11 to 12 g (0.39 to 0.42 oz). The species is sexually dimorphic. Adult males have a shiny emerald-green head with a conspicuous yellow eye-ring. Their throat and upper breast are the same green. Together they are bordered by a wide yellow collar with a thin chestnut line between the two colors on the side of the breast. Their mantle, back, upperwing coverts, and tail are shiny emerald-green and their rump and uppertail coverts bright yellow. Voice: The yellow-collared euphonia in flight often makes a "nasal and plaintive call...a drawn-out peeeeeeee, sometimes interspersed with short, clear, winh calls". It also makes "soft pek notes" while foraging.
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: Chestnut-breasted Chlorophonia and Yellow-collared Chlorophonia.