Twenty-one native species of land snails were recorded during a survey of the Aydin Mountains in the Province of Aydin, Turkey. Idyla aydinensis Orstan (Pulmonata: Clausiliidae) is described as a new species from an altitude of 1030 in. The new species is characterized by a narrow shell with closely spaced fine ribs and a long penis with a grooved pilaster. New records of Turanena hemmeni, Zonites chloroticus, Xeropicta smyrnocretica and Helicigona matrella are given, extending the ranges of these species.