Die Verbreitung seltener Mondrauten-Arten in Südtirol und dem angrenzenden Trentino

From 1992 to 2004 the rare species Botrychium lanceolatum, B. matricariifolium and B. multifidum have been observed in South Tyrol (Province of Bozen/Bolzano, Italy). In addition to confirming long known localities, several new ones have been found. These observations are listed together with further unpublished records from the 1980 s and 1990 s as well as with data known from literature. The herbarium collections of the Tiroler Landesmuseum Ferdinandeum (IBF) at Innsbruck and the Natural History Kabinett Vinzentinum Brixen (at present in IBF) have also been investigated. Furthermore, all known sites of the three mentioned Botrychium species as well as the species Botrychium simplex and B. virginianum in the neighbouring Province of Trento are listed and discussed regarding the total distribution as well as the range of these ferns in Italy. After 1990, B. lanceolatum has been confirmed in South Tyrol from two localities, while B. matricariifolium was known only from one and B. multifidum from four sites. Investigations at two South Tyrol sites have shown that the places where Botrychium species can usually be found are Nardus communities (Geo montani-Nardetum strictae) rather poor in species on humus-rich, strongly acidic and very poor soils. The elevations of the Botrychium sites range from 1320 m to 1900 m a.s.l. with the exception of one locality of B. matricariifolium. Due to the very small populations and the documented decline as well as to existing threat factors for the three listed Moonwort species in South Tyrol all of them are “critically endangered”. Activities for protection and the initiation of a conservation project for these rare ferns are highly necessary.