On Trochoidea geyeri (Soós, 1926) and some conchologically similar taxa (Mollusca: Gastropoda Pulmonata: Hygromiidae)

To provide background information for a proposal to the International Commission on Zoological Nomenclature to suppress five subjective senior synonyms of Trochoidea geyeri, the synonymies of this and some other hygromiid species are given. The nominal taxa that are dealt with concern species that are conchologically more or less similar. These species were studied to minimize the risk that even more unused senior synonyms of T. geyeri would be discovered, which would require an additional ruling of the Commission. Distributional data and short conchological diagnoses are added to increase the usefulness of the present paper.