Michael Murnane is a concept artist/sculptor, and the author of the short story "Wat Tambor and the Quest for the Sacred Eye of the Albino Cyclops" in Star Wars: Visionaries. His work can be seen in The Art of Star Wars Episode II: Attack of the Clones and The Art of Revenge of the Sith.
Sources[]
Clay Characters: An Interview with Mike Murnane on StarWars.com (content now obsolete; backup link)
Meet the Episode III Art Department on StarWars.com (content now obsolete; backup link)