Until now, Dryopteris remota was only recorded in the Czech Republic from the Moravian Karst, ca 70 years ago. This record is mentioned in some studies, but references to the data’s origin have always been missing. For this reason it was uncertain whether D. remota was still present in the Czech Republic. Recently, the records from the Moravian Karst were verified by re-examination of original herbarium specimens. In 2002 a specimen of D. remota was found for the first time in Bohemia, close to the village of Ktiš, on a slope of Malý Plešný hill in the foothills of the Bohemian Forest (S Bohemia). At this locality only one plant occurred on the boundary between Lonicera nigra-shrub and spruce-beech-fir forest, on a gneiss outcrop. Determination of the Czech specimens of D. remota was based on comparisons with macro- and micromorphological characters of both Alpine (Upper Austria) and Carpathian (West Ukraine) specimens, as well as descriptions in the literature. A detailed morphological description and comparison with similar taxa are included. A map of its distribution within the Czech Republic as well as a map of the distribution of D. remota worldwide is also presented. It is suggested that D. remota be designated a critically endangered plant species in the Czech Republic.
The agamosporous and taxonomically critical Dryopteris affinis group was investigated as part of a cytogeographic and morphometric study of ferns in Central Europe. Material from 27 localities in the Czech Republic, Slovakia, Poland and Austria was sampled and evaluated using both morphometric multivariate and karyological analyses. Chromosome counts and flow cytometric analyses revealed the existence of two distinct triploid taxa (2n = 123) of differing genome size, which correspond to D. borreri and D. cambrensis, and of a rare pentaploid hybrid (2n = 205) D. ×critica (D. borreri × D. filix-mas). Morphometric analyses confirmed a clear separation between both triploid taxa. New quantitative characters were selected based on a discriminant analyses, and a key for the identification of the species is presented.