The vermilion flycatcher (Pyrocephalus obscurus) is a small passerine bird in the tyrant flycatcher family found throughout South America and southern North America. It is a striking exception among the generally drab Tyrannidae due to its vermilion-red coloration. The males have bright red crowns, chests, and underparts, with brownish wings and tails. Females lack the vivid red coloration and can be hard to identify—they may be confused for the Say's phoebe. The vermilion flycatcher's song is a pit pit pit pidddrrrreeedrr, which is variable and important in establishing a territory. Riparian habitats and semi-open environments are preferred. As aerial insectivores, they catch their prey while flying. Their several months-long molt begins in summer.
It is strongly dimorphic. Males are bright red, with contrasting dark brown plumage. Females are drab and have a peach-colored belly with a dark gray upperside. The reddish color varies, but can be vermilion, scarlet, or orangish. In males, the crown, chest, and underparts are red. The lores (region in front of the eyes), nape, ear coverts, wings, upperparts and tail are all brown to blackish brown. The female has a grayish crown, as well as grayish ear coverts, wings and tail. The flight feathers and wing coverts are slightly paler gray, which create a barring effect. The supercilium (eyebrow) is whiter. The underparts start white but become light red moving downward. Juveniles of both sexes look similar to adult females; juvenile males have much brighter red underparts, whereas juvenile females have yellowish underparts. Plumage appears constant throughout the year for both adult sexes and for juveniles. They have a slight crest, which can be raised when needed. Males are not easily mistaken for other species, but the drab females may be confused with the Say's phoebe.