Discovery of the gametophytes of Trichomanes speciosum (Hymenophyllaceae: Pteridophyta) in Poland and its biogeographical importance

Gametophytes of Trichomanes speciosum Willd. (Hymenophyllaceae: Pteridophyta) have been reported for the first time in two localities in the Westsudetian Highland, Lower Silesia, SW Poland. They form the easternmost outposts of this taxon in Europe, suffering the most severe climatic conditions in the extent of its occurrence. On both sites gametophytes occur in horizontal rock fissures in Upper Cretaceous sandstone, surrounded by degraded eastern oak-hornbeam forests. The gametophytes are very small (up to 2cm diameter) and sparse.