Red-list of Italian bryophytes. 1. Liverworts and hornworts.

The objective of this study is to provide an updated conservation status of all liverworts and hornworts in the Italian territory, evaluated according to IUCN’s Guidelines for Application of IUCN Red List Criteria at Regional Level. Overall, 27.4% of taxa assessed in this study are assigned to a risk category and, therefore, considered threatened in Italy. Four liverworts are considered as Extinct, two liverworts and one hornwort Possibly Extinct at regional level. Moreover, a further 9.8% are assessed as Near Threatened, 10.8% as Data Deficient and 49.7% as Least Concern. Most threats are co-occurring, indicating that many taxa are subjected to a set of correlated adverse processes. The main IUCN major threats identified were natural system modifications (i.e. dam construction, increases in fire frequency/intensity, and water management/use), climate change (mainly increasing frequency of droughts and temperature extremes), agriculture (including pollution from agricultural effluents) and aquaculture.