Odd, dark blue-and-gray cuckoo with a bright yellow bill. Found in thick habitats including forest, forest edge, and thickets. Skulks in the thickest parts of the mid-story, especially preferring vine tangles. Call starts with a hesitant series of high “kik” notes, eventually followed by a long, accelerating trill. Also gives a long up-and-down whistle. Dark coloration and yellow bill are distinctive. Range does not overlap with the similar Green Malkoha.