The Streamer-tailed Tyrant is a distinctive resident of Buriti palm groves and seasonally wet grassland from western Bolivia to central Brazil and to northeastern Argentina. Overall these birds appear pale gray with black wings that are highlighted by a patch of cinnamon at the base of the primaries. Aptly named, the Streamer-tailed Tyrant has a long deeply forked tail. Streamer-tailed Tyrants often perch conspicuously on the tops of low trees and bushes and utter a harsh repeated "wurreep" call. They forage by flying low over marshy areas before pouncing to the ground to catch large arthropods.
During courtship, the members of a pair of Streamer-tailed Tyrants perch 10-50 cm apart facing one another, while each bird alternately lowers their head and raises and fans their long tail. The birds then proceed to lower their tail and raise their heads while raising their wings and calling continuously.