Clithon retropictumClithon retropictum is a species of freshwater and brackish water snail with an operculum. It is an aquatic gastropod in the family Neritidae.DistributionThis species occurs on the Japanese islands of Honshu, Kyushu, and Shikoku. It also occurs on the South Korean island of Jeju, and in Taiwan.HabitatC. retropictus lives in brackish water and in freshwater.Feeding habitsClithon retropictum is an herbivorous species.Life cycleC. retropictum is oviparous. Juveniles hatch from eggs in September. The lifespan of C. retropictum is up to 12 years and it is one of the most long-lived freshwater gastropods.Parasites ''Vibrio parahaemolyticus''StatusThe species is considered as a second grade endangered species by the Korean ministry of environment.