Heat a medium nonstick skillet over medium-high heat. Coat pan with cooking spray. Add shrimp and 1/4 teaspoon salt; cook 4 minutes or until shrimp are done, turning once. Remove from the pan. Coarsely chop shrimp.
Combine corn and the next 5 ingredients (through jalapeño) in a medium bowl. Gently stir in the shrimp. Combine juice, oil, and remaining 1/4 teaspoon salt, stirring with a whisk. Drizzle juice mixture over shrimp mixture; toss gently to coat. Divide lettuce among each of 4 plates; top with shrimp mixture. Sprinkle evenly with toasted coconut.