Wikipedia
Malunga
The malunga is a single-stringed musical bow played by the Siddi of India, who are the descendants of East African immigrants. It produces two tones, an octave apart, and the knuckle of the hand supporting the instrument may also presses against the string to vary the pitch. It is struck with a stick and, as with the berimbau of Brazil, the hand holding the stick also holds a rattle (in the case of the malunga the rattle, called mai misra). The malunga has a gourd resonator which amplifies the instrument's sound. The placement of this rattle along the string also varies the pitch produced by the Malunga.