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Four Volcanic Islands, scattered in the Pacific west of Mexico, make up the island group named after Don Juan Vicente de Guemes, 2nd Count of Revillagigedo. They are also called "the Mexican Galapagos." The only inhabitants: a military garrison on the largest rock, housing about 250 people. There is no reliable source of fresh water on any of the islands.
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San Benedicto is the largest of the island group. It was first called Santo Tomas, but that changed with explorers "re" discovering it.
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San Benedicto
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Socorro was originally called Innocentes. A second explorer "rediscovered" it and named it Isla Anublada (Cloudy Island), and then it was rediscovered again and renamed to Isla Socorro (after "Virgen del Perpetuo Socorro).
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Clarion is semiarid to arid throughout, but like all the islands in this archipelago, has a vibrant underwater profile. The Clarion Angelfish (a juvenile one in the picture - they lose the blue striping when the mature) is endemic to the region. Clarion was originally named Santa Rosa, but was rechristened after the name of the vessel commanded by the explorer that discovered it.
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Finally there is Roca Partida - broken rock. No name change for this volcanic chunk poking up out of the sea, no vegetation, the occasional shorebird, and only 3.5 acres in area.
It sounds quiet, doesn't it?