The Many-coloured Rush-tyrant (Tachuris rubrigastra) is a small passerine bird of South America belonging to the tyrant flycatcher family. It is the only member of the genus Tachuris and its relationships with the other members of the family are uncertain.

Tachirus rubrigastra nest

It is a small dumpy bird, 10.5 cm in length. The tail is short, the wings are short and rounded and the bill is slender. As the bird's name suggests, the plumage is very colourful. The back and rump are green while the underparts are yellow apart from the white throat, black breastband and red undertail-coverts. The face is dark blue-grey, there is a yellow stripe over the eye and the crown is dark with a red patch that is often concealed. The wings and tail are dark with a white wingbar and white outer tail-feathers. Juveniles are considerably duller than the adults.

There are four subspecies: T. r. rubrigastra is the most widespread, occurring from south-east Brazil to southern Argentina and central Chile. T. r. alticola is found in the Andes of south-east Peru, west Bolivia and north-west Argentina. T. r. libertatis is found in coastal Peru while T. r. loaensis is restricted to Antofagasta Region in northern Chile.

It inhabits marshland and reedbeds around lakes and rivers. It is particularly associated with stands of Scirpus. The nest is built among plant stems.