Dicranum scottianum Turner (Dicranaceae): synonyms, a type and the correct author

ABSTRACTIntroduction. The moss Dicranum scottianum Turner, described based on material collected in Ireland by Robert Scott, is currently known from Europe and Macaronesia (Canary Islands and the Azores). The previously proposed authorship of ‘Turner ex Robt. Scott’ and lectotype for this name proved to be erroneous.Methods. Over 60 herbarium specimens, including types, of D. scottianum and putative allies were examined with the aim of outlining the diagnostic features of the taxon or taxa concerned, and establishing any necessary synonymy.Key results. The true authorship of Dicranum scottianum by Turner is re-established, and the name is effectively lectotypified with extant original material from BM. The type specimen and some subsequent collections of the species are described and illustrated. New nomenclatural synonyms of D. scottianum (namely Dicranum canariense Hampe ex Mull.Hal., D. erythrodontium Hampe ex Mull.Hal. and Orthodicranum allorgei J.J.Amann & Loeske) are detailed.Conclusions. Dicranum s...