-

There are some freshwater gastropods involve in the life cycle of parasitic trematodes. Therefore, some of these animals, such as Lymnid snails and planorbid gastropods are very important in term o public health and veterinary. For this reasons, a comprehensive snail search had been undertaken in two successive mollusc surveys in the summer of 1989 & June 1999, repectively. Freshwater
gastropods search done through a grant supported financially bythe Tehran Medical Sciences University, School of Public Health & Institute of Public Health Research and technically in part by the British Natural History Museum & Danish Bilharziasis Laboratory. Wide varieties of shells and aquatic molluscs were collected from different water bodies. Shells and animals of different taxa sorted as much as possible. Shells put into the suitable jars and labelled versus snails killed first in boiling water & / or minthol, then transferred into the container enclosing 70 % ethanol and labeled. Labelling include name of collector, name of locality and date of collection on a piece of tracing paper with a pencil. Study of shells, living mollusc morphology and anatomic characteristics of alcohol materials used for differentiation. During the snail search, 6 prosobranch taxa identified against 7 pulmonated snails including Anisus vortex (L. 1758). and Falsipyrgula bakhtarana nov. sp. contributed as new species for Iran and zoological world, respectively