A chordophone is a stringed instument such as a harp or guitar. In terms of the african instrument that falls under this catagory, you would be looking at an instrument called a Kora. A Kora is sort of like a guitar.
Membranophones-
A membranophone is any musical instrument which produces sound primarily by way of a vibrating stretched membrane. All african drums beside the slit drum falls within the catagory of african membranophones.
Aerophones-
The word aerophone refers to a wind instrument. An african instrument that represents the aerophones would be an archaic bull-roarer. You use this intrument by whriling it around to the air to produce a whistling sound.
An art movement is a tendency or style in art with a specific common philosophy or goal, followed by a group of artists during a restricted period of time, or, at least, with the heyday of the movement defined within usually a number of years.