Endangered species were indicated in the Checklist using the letter M ('minacciata' in Italian). More than 500 threatened species and subspecies are listed in the Checklist, less then 1% of our fauna. This approach is probably largely subjective, and the choice biased toward certain taxa (butterflies, carabid beetles, snails) extensively sampled by specialists; other taxonomists indicated few or no species probably because of the lack of available data. STOCH (2003), analizing the updates to the Checklist, calculated the percentage of vulnerable and threatened species, obtaining a value close to 10% of the terrestrial and freshwater species richness. Following the indications given by the taxonomists involved in the project "Distribution of Italian invertebrates", 1076 species and subspecies (14% of overall species+ subspecies richness considered in the project) may be grouped in the following IUCN categories: presumably extinct (43 species), endangered (384) and vulnerable (640). These species may be defined as “species of national interest”; using these criteria together with rarity and endemism it will be possible to compile a correct Italian “red list”.