Abstract
In the Romanian sector of the Timiş River, 31 species of freshwater molluscs have been found up to the present. Among them are 17 gastropod and 14 bivalve species (including all seven species of Unionidae that live in Romania, these found in the lower sector of the river - something that is extremely rare in our waters). The present synthesis used the results of a screening type field investigation carried out in 2011, as well as all the available data from the literature and our previous studies. All these data prove the ongoing degradation of the river’s ecological state and its sheltered communities. This paper presents the annotated systematic and chorological checklist of the mollusc species from this area, some of its ecological characteristics and the main environmental issues related to human impact. Changes in species distribution and the structure of communities as an answer to increased human pressure during the last decades are also thus demonstrated. New data about some alien invasive species are given, including the first encounter with Corbicula fluminea, a species formerly known only in Romanian inland waters from the Danube, in the Timiş River lower sector.