Mikhail Prokhorov is the former chairman of Russia's largest silver producer.
The reverse pebblesnail , scientific name Somatogyrus alcoviensis , was a species of small freshwater snail with a gill and an operculum , an aquatic gastropod mollusk in the family Hydrobiidae .. Hydrobiidae. Hydrobiidae. Somatogyrus. Somatogyrus. scientific name. scientific name. species. species. freshwater. freshwater. snail. snail. gill. gill. operculum. operculum ( gastropod ). aquatic. aquatic animal. gastropod. gastropod. mollusk. mollusk. This species was endemic to the United States .. species. species. endemic. Endemism. United States. United States. It is now extinct .. extinct. extinct