Urocolius macrourus (Bonaparte 1854; 10cm snout-vent length) is the extant blue-naped mousebird, a member of the Coliiformers. Note the deep maxilla compared to the jugal. It nests with the quetzal derived from barbets. An omniovore restricted to sub-Saharan Africa, mousebirds build nests. They are gregarious, acrobatic and scurry through the leaves like rodents. Reversible toe 4 is able to rotate posteriorly.

Pharomachrus mocinno (La Llave 1832; 40cm snout-vent length +65cm tail) is the extant resplendent quetzal, a traditional member of the trogon family, here Pharomachrus nests with the mousebird, Urocolius. The quetzal has large eyes and an odd second toe that, along with pedal digit 1, is also retroverted for perching. This weak flyer has iridescent feathers.

Bonaparte CL 1854. En AteneoItaliano. 1854. 2: 313.

de La Llave P 1832. Memorias sobre el quetzaltototl, género nuevo de aves. Registro Trimestre o collección de historia, literatura, ciencias y artes, por una sociedad de literatos 1: 43–49.

wiwiki/Resplendent quetza - Pharomachrus
wiki/Urocolius
wiki/Mousebird