Rudarius ercodes, the whitespotted pygmy filefish, is a species of reef filefish in the family Monacanthidae. It is a small fish, growing to only 5 cm (2 in), and is found in the temperate waters of Japan. It is kept in captivity and has been successfully captive bred.

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Monacanthidae
Fish of East Asia
Fish described in 1902
Taxa named by David Starr Jordan