Could it possibly be an aberrant Blue-Green Chromis (Chromis viridus)? Yellow body with some greenish blue speckling, greenish blue caudal peduncle and black caudal fin. Seen at Cairns Aquarium, housed with other Blue-Green Chromis, this individual was the only one with this odd colouration in the tank, but another tank has another aberrant C. viridus (different colouration from this one).
