Of the family Helicidae (Gastropoda, Pulmonata) from northwestern Spain, 20 spp. were tested as hosts for D. dendriticum in experimental conditions. The relationship between egg hatching in the digestive tract and the development of sporocysts (108-110 days after egg ingestion) was studied. Three species are new intermediate hosts of this trematode: Candidula intersecta, Helicella corderoi and H. jamuzensis. The ecological value of the positive species in the life cycle of the parasite is discussed.