Luzon Island, Philippines
Lionfish (Pterois species, this one is around 7 inches in length) are among the more toxic predators of the reef-- their dorsal fins (top along spine) are hollow barbs capable of injection poisonous venom into a predator unfortunate enough to approach too closely. Typically they assume a fanned-out, fins-erect posture when approached by a potential predator such as a diver, pointing the dorsal fins toward the threat.
Jeffrey N. Jeffords (photographer; copyright holder; identification)
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