UNICORN FILEFISH juvenile
Aluterus monoceros (Linnaeus, 1758)
    Jeff Hill of Kailua-Kona, Hawaii, snapped this rare photo of a juvenile Unicorn Filefish drifting in association with a jellyfish of the genus Thysanostoma. Jeff describes his find in his delightful Kona fish watching blog: http://konafishwatching.blogspot.com/ Scroll down to the October 1, 2012 entry. The ID was made by Bruce Mundy, a biologist at the National Marine Fisheries Service Honolulu Laboratory.

The Unicorn Filefish resembles the common Scrawled Filefish (Aluterus scriptus) but has a shorter tail fin and is plain gray without markings when fully grown. Young juveniles, as seen here, are strikingly patterned. The markings fade with growth. The species occurs in all warm seas, but sightings in Hawaii are few and far between. My "Ultimate Guide" fish book has a photo of an adult taken in an aquarium but here's a better one taken in the wild off O`ahu by Jeff Milisen. Adults attain about 30 in.