The male spotted boxfish (top) is blue with orange highlights and white spots along the back, whereas the female (second photo) is a fairly uniform brown with white spots all over. Despite their shape, boxfishes are nimble swimmers boasting a good turn of speed and surprising maneuverability.

I got these photos because the male boxfish came up to check me out a couple of times and the female was unperturbed by my presence as she searched for food on an old pier piling.