Preheat oven to 400°. Heat olive oil in a large saucepan over medium heat. Add onion and next 3 ingredients and cook, stirring often, 5 to 7 minutes or until tender. Stir in rice and next 3 ingredients. Stir in broth.
Pour mixture into a lightly greased 13- x 9-inch baking dish. Cover and bake 35 to 40 minutes or until most of the liquid is absorbed.
Remove from oven. Stir in artichokes, tomato, and parsley. Scatter mussels over top and bake, uncovered, 10 to 12 minutes or until mussels open. (Discard any that do not.)