explosionsoflife:

Unlike most other eels, ribbon eels (Rhinomuraena quaesita) change color and sex during their life. Juveniles are nearly black with a yellow dorsal fin. As they mature, the black becomes bright blue and the snout and lower jaw turn yellow. This is the male color stage. When they reach a body length of about 1.3m, the males turn yellow and become fully functional females, which lay eggs. Ribbon eels live on coral reefs, mostly hiding in crevices. They have leaflike nostril flaps, which sense vibrations in the water.
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