Place garlic and a pinch of salt on work surface. Mash into a paste using the flat side of a chef's knife.
In a medium bowl, stir together garlic paste and Worcestershire sauce; season with salt and pepper. Add fish, and gently toss to coat. Let marinate for 10 minutes.
Add flour to bowl, and gently toss until each piece of fish is lightly coated.
Heat 2 inches of oil in a heavy-bottomed pan over medium heat. Test oil with a small cube of bread; it will sizzle when oil is hot enough to fry. Working in small batches, shake off any excess flour and add fish to oil; do not overcrowd the pan. Cook until golden brown, turning halfway through, about 6 minutes. Using a slotted spoon, transfer fish to a paper towel-lined plate to drain; repeat with remaining fish.
To serve, evenly spread a dollop of tartar sauce on a tortilla; top with cucumber, 3 or 4 pieces of fish, arugula, cilantro, and 1 teaspoon of zest. Fold right side of tortilla over filling, and roll to enclose filling, leaving one end open. Repeat with remaining ingredients. Serve with additional tartar sauce and lime wedges.