Yellow-thighed Brushfinch

The yellow-thighed brushfinch (Atlapetes tibialis) is a passerine bird in the family Passerellidae, the New World sparrows. It is found in Costa Rica and Panama. == Taxonomy and systematics == The yellow-thighed brushfinch has a complicated taxonomic history. It was formally described in 1864 with the binomial Tachyphonus tibialis. For a time later in the nineteenth century some authors placed it in genus Buarremon. In 1898 Robert Ridgway erected genus Pselliophorus and named tibialis as the type species. The species' further taxonomy is unresolved. In 2019 the American Ornithological Society and the Clements taxonomy merged Pselliophorus into Atlapetes. The IOC followed suit in 2020 and the first version of AviList followed them in 2025. However, as of late 2025 BirdLife International's Handbook of the Birds of the World (HBW) retains the species in Pselliophorus. The yellow-thighed brushfinch is monotypic. == Description == The yellow-thighed brushfinch is about 18 cm (7.1 in) long and weighs 27 to 35 g (0.95 to 1.2 oz). The sexes have the same plumage. Adults have puffy lemon yellow feathers on their tibiae that give the species its English name. They have a black crown. The rest of their head and their upperparts are sooty slate…