Killarney fern Trichomanes speciosum Willd. in Poland (2002–2008) – the state of population and protection perspective

Killarney fern (Trichomanes speciosum Willd., Hymenophyllaceae) is one of the most endangered and interesting ferns in Europe, which forms exclusively independent gametophyte colonies. In Poland, it has been reported in two localities in the Westsudeten Foothills, Lower Silesia. They are the most eastern outposts of this taxon in Europe, suffering the most severe climatic conditions in the extent of its occurrence. In both sites, gametophytes occurred in horizontal rock fissures in the Upper Cretaceous sandstone, surrounded by degraded eastern oak-hornbeam forests. The analysis of its occurrence in Poland during sixth years showed dynamic changes of the population state. The population which occurs in the cave near Złotoryja has decreased between 2002 and 2006, to be almost extinct, but in the last two years its cover increased to half of its previous state. Gametophytes found in the locality near Lwówek ŒŚląski (Panieńskie Skały) in years 2002–2004 have not been confirmed in 2008.