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Giant Spider Crab
As if bathed in moonlight, a giant spider crab (Macrocheira kaemferi) is illuminated by a diver's lamp in Japan's Izu Oceanic Park. Protected from some predators by its hard exoskeleton, the creature—which can grow to ten feet (three meters) wide—can also blend in with the ocean floor. Under deeper cover, it can disappear beneath the sponges and other marine life it uses to adorn its shell.
Photograph by David Doubilet, National Geographic

Giant Sea Creatures

See giant sea creature photos, from National Geographic.