Onychorhynchus sp., a small songbird, is the general name of four species of birds of the genus, which is a monomorphic genus. In the previous classification system, a single species was divided into four subspecies. 1993 was identified as four independent species. The male of the Yellow flycatcher has a gorgeous crest and expands into a transverse fan. The female feather is very short. The beak is flat and wide, the structure and muscle of the vocal tube are complex, and the sound is changeable and pleasant; Off toe foot, with three toes, one front and one rear, and the rear toe is the same length as the middle toe; The legs are thin and weak, and the scales on the posterior edge of the tarsometatarsus often heal into a whole scale plate; Sparrow palatine skull.
It mainly feeds on flying insects, such as dragonflies and butterflies. Activity alone or in pairs in wetlands or forests. The nest is exquisite, and the chicks are late. It is distributed from the south of North America to the Amazon rainforest and the southeast corner of Brazil. It lives in humid areas such as tropical rainforest.