It looks like a Sunset Fairy Wrasse. I just bought one a couple of weeks ago and it is a sweet fish and very peaceful. Below is the description from
www.aquacon.com
Sunset Fairy Wrasse
(Cirrhilabrus Sp)
Brand new discovery from the Marshall Islands.
Now available to the marine hobbyist!
Description: This is it. Introducing the Sunset Fairy Wrasse. Named from the beautiful coloration that looks like the coming of a beautiful sunset with the yellow and red skys joining with streaks of sky blue added for accent. Jump on one of these, and you will be glad you did! It is a very peaceful wrasse and can be housed with a wide variety of reef fish, including other small fairy wrasse species. Totally harmless to corals, clams, and ornamental invertebrates, It will help to control pyramidellid snails, and flat worms which are harmful to clams. Like all Cirrhilabrus Fairy Wrasse's, provide with plenty of live rock and live sand.
Temperament: Easy going, mellow fish. Gets along with all other tank inhabitants.
Recommended Tank size: The Sunset Wrasse prefers a tank of at least 50 gallons with plenty of places to hide & swim.
Food and diet: Feed a varied diet of frozen prepared foods, minced fresh shrimp, and a good flake food. Try to feed at least twice a day.
Reef Compatability: Excellent. No threat to corals or ornamental invertebrates. Large individuals may feed on smaller, delicate shrimps. It will aid the reef aquarist in controlling pyramidellid snails and commensal flatworms.
Hardiness: this is a moderately hardy fish.
Care Level: Easy.
Approximate Purchase Size: 3" to 4"