Marty’s photo of the day #4949: Golden spadefish undergo significant physical changes as they age. Juveniles have long, crescent-shaped dorsal and anal fins, while adults have shorter, rounded fins and a spade-like body. An interesting behavior is that juveniles sometimes float sideways, mimicking dead leaves, to hide from predators. Adults, like the one in this photo are quite large, reaching 19 inches across.
(Photographed in the Raja Ampat of Indonesian New Guinea.)