purple chokeberry

Aronia × prunifolia, called the purple chokeberry, is a North American hybrid shrub of Aronia arbutifolia × Aronia melanocarpa in the rose family. It is native to eastern Canada and to the eastern and central United States, from Nova Scotia west to Ontario and Wisconsin, south as far as western South Carolina with an isolated population reported in southern Alabama.

Some authors consider this to be a hybrid rather than a full-fledged species but it does grow in places where neither parent is present (most of Michigan for example). This independence merits acceptance as a full species. This sort of thing is not unusual; many species of plants originated as hybrids.