Angel Ledge, Midway Atoll, 75 feet

Makapu'u tidepool, Oahu

Haleiwa Trench, Oahu, 15 feet

Kaiona, Oahu, 3 feet

Brown to black with light margins, quite variable.  Locally abundant on seaweed.  Attains 3/4 inch.  Worldwide in warm and temperate seas.