1In large bowl, mix yogurt, mayonnaise, tarragon, salt and garlic. Stir until well blended. Stir in crab, artichoke hearts, celery and green onions. Cover and refrigerate about 30 minutes to blend flavors.
2Heat 10-inch skillet over medium-high heat. Brush melted butter on cut sides of rolls. Place cut sides down in skillet; cook about 2 minutes or until toasted.
3Place rolls on plates; fill with lettuce and crab mixture. Serve with lime wedge.