Rediscovery of Armiger crista (Linnaeus, 1857) (Gastropoda Planorbidae) in Algeria

Armiger crista (Linnaeus, 1758), a holartic freshwater gastropod, has been rediscovered inAlgeria. It was found in a small lake whose malacofauna was almost exclusively paleartic/ho-lartic. This aquatic environment is probably unique in the Maghreb, where cold-climate faunal elements are rapidly disappearing due to global warming. Monitoring of the site and study ofother groups is highly recommended.