No, this is not an alien spaceship from another world—it is a baby file clam (Lima sp.). File clams have long tentacles that protrude from their shells—like this closely-related flame shell—which are still growing on this juvenile clam. They are used for swimming, which they do by clapping their shells together), and if a predator takes a bite, the clam can drop those tentacles to make a quick escape. The image, taken at 10x zoom, took 12th place in the 2010 Nikon Small World photomicrography competition.
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