Rub a lime wheel around the rims of two martini glasses to moisten. Spread a layer of salt in a saucer. Press the rims of the glasses into the salt to form salt rims.
In a cocktail shaker filled with ice, combine the tequila, lime juice, lemon juice, orange juice, orange liqueur, agave and 1/2 ounce water. Shake for 10 seconds, then strain into the martini glasses. Garnish each with a hibiscus flower and a lime wheel. Serve.