1. Heat oil in a large Dutch oven over medium-high heat. Add fennel and next 3 ingredients (through garlic); sauté 5 minutes or until fennel is tender. Add wine; cook, uncovered, 2 minutes. Stir in oregano, red pepper, and tomatoes. Bring to a boil; cover, reduce heat, and simmer 10 minutes. Add clam juice; return to a simmer.
2. Add fish; cover and cook 3 minutes. Add clams and mussels; cover and cook 5 minutes or until shellfish open, adding shrimp in last 3 minutes of cooking time. Discard any unopened shells. Remove from heat. Discard thyme sprigs, and ladle seafood evenly into 8 shallow bowls. Ladle broth evenly over seafood. Sprinkle evenly with parsley.