A closing cap for a discharge head of a medium container, having a bottom part having locking edges and a latch boss, the bottom part fastened to a container neck and detachably latched to a top part having a rim portion which overlaps the bottom part and has locking edges which can be brought into engagement with the locking edges of the top part, as well as a locking arm, having a locking edge, which can be latched behind a latch boss.