The short-crested flycatcher (Myiarchus ferox) is a species of bird in the tyrant flycatcher family Tyrannidae. It is found in every mainland South American country except Chile. The short-crested flycatcher was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it with the Old World flycatchers in the genus Muscicapa and coined the binomial name Muscicapa ferox. The specific epithet ferox is from Latin and means "brave", "wild" or "fierce". Gmelin based his description primarily on "Le tyran de Cayenne" that had been described in 1760 by the French zoologist Mathurin Jacques Brisson. Brisson had examined both male and female specimens that had been sent to France from Cayenne.
The short-crested flycatcher is one of 22 flycatchers in the genus Myiarchus that was introduced in 1844 by Jean Cabanis. Within Myiarchus, the short-crested flycatcher is genetically closely related to the Panama flycatcher (Myiarchus panamensis).
As of early 2025 the short-crested flycatcher is assigned these three subspecies: