Altogether, 78 terrestrial mollusc species were recorded on 31 plots in a stretch of the Tichá Orlice River valley between the cities Choceň and Letohrad (East Bohemia, Czech Republic) in 2007 and 2009. This region harbours 46% of the total terrestrial mollusc fauna of the Czech Republic.
The fairly high species richness corresponds to a high habitat diversity and species pool of the region that includes Alpine and Carpathian elements. Of prime conservation importance is a high share of rare and endangered species (EN-2, VU-9, NT-14 species) and species mostly having an isolated population there from the main distribution range.
This region is a real hotspot of forest gastropods in Transalpine Europe.