Discard tough leaves and woody base of lemongrass. Thinly slice the tender portion of the lemongrass stem. In the base of the steamer, combine lemongrass, juices and ginger; bring to boil. Arrange skate on steamer rack of basket, fit into pan, cover tightly. Reduce heat; steam for 5 minutes or just until skate "flakes" easily when tested with a fork. If rack will not hold all of the skate at one time, steam in two batches.
Using a wide slotted spatula, carefully transfer skate from steamer rack to heatproof platter or individual serving plates; keep warm. Turn heat to high, cook juices, uncovered, for 10-15 minutes or until sauce is reduced by one-half.(Should have consistency of syrup.) Strain sauce over fish. Garnish with lime slices and chive stems. (Note: Narrow strands of lemon grass can be substituted for chives, but may be too fibrous to be edible.
