The smallest roller in the region and the only one that appears dark with a bright yellow bill. In flight, it shows a blue tail with dark central stripe and purple underwing coverts.
Juvenile resembles adult but is duller and has greenish underparts streaked with black; bill is bright yellow as in adult.
Riverine forest and adjacent savanna, with a preference for perching an breeding in dead trees.
Harsh screams and cackles.