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 , 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. Despite being socially monogamous, vermilion flycatchers will engage in extra-pair copulation. They also practice within-species brood parasitism, whereby females lay their eggs in the nest of another individual. Females build shallow open cup nests and incubate the brown-speckled whitish eggs. The male feeds the female during incubation. Two broods of two or three eggs are laid in a season lasting from March through June. Once hatched, both males and females feed the chicks, which are ready to fledge after 15 days. The species was first described in the late 1830s as a result of the voyages of Charles Darwin. The taxonomy of the genus Pyrocephalus was revised in 2016, which led to the identification of several new species from the vermilion flycatcher's subspecies, including the now-extinct San Cristóbal flycatcher. Populations have declined because of habitat loss, though the species remains abundant. The overall population numbers in the millions, thus the International Union for Conservation of Nature considers it a species of least concern. Taxonomy and systematics The tyrant flycatcher family, Tyrannidae, is a group of passerine birds present only in the Americas; its members are generally drab in coloration. Within it, the subfamily Fluvicolinae comprises the genera Pyrocephalus, Contopus, Empidonax, and Sayornis. They likely share a common ancestor that belonged in the genus Contopus or Xenotriccus and later diversified. The Pyrocephalus are most closely related to Sayornis in terms of morphology, but genetic analysis shows they may be more closely related to Fluvicola. The first description of the vermilion flycatcher was in 1839 by John Gould, who created the current genus Pyrocephalus, and designated his find as Pyrocephalus obscurus. The identification was based on specimens brought back by Charles Darwin on the second voyage of HMS Beagle, which lasted from