Checklist of gypsophilous vascular flora in Italy.

Our understanding of the richness and uniqueness of the flora growing on gypsum substrates in Italyhas grown significantly since the 19th century and, even today, new plant species are still being discovered.However, the plants and plant communities, growing on gypsum substrates in Italy, are still arelatively unknown subject.The main aim of this paper was to elaborate a checklist of the Italian gypsophilous flora, to increaseknowledge about this peculiar flora and for which conservation efforts need to be addressed.Through a structured group communication process of experts (application of the Delphi technique),a remarkable number of experienced Italian botanists have joined together to select focal plant specieslinked to gypsum substrates. From the results obtained, 31 plant species behave as absolute or preferenttaxa (gypsophytes and gypsoclines) and form the ‘core’ Italian gypsophilous flora. The most abundant lifeforms were chamaephytes and hemicryptophytes, belonging to Poaceae and Brassicaceae; as for chorotypes,the most represented are Mediterranean and narrow endemics. By improving on previously available informationabout the flora with a clear preference for gypsum in Italy, this undertaking represents an importantcontribution to the knowledge of a habitat which is today considered a priority for conservation.