Eleven plants of Asplenium platyneuron (ebony spleenwort) were found in disturbed serpentine woodland in south-central Slovakia (Central Europe). This find represents a new addition to the fern flora of Europe. It is probably the result of long-distance spore dispersal. The nearest known sites for this species are those in eastern North America, about 6500 km away. The important determination characters of A. platyneuron are described, the Slovakian locality characterized and an overview of the ecology and a map of the worldwide distribution of this species provided.
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.
A detailed cytogeographic and morphometric study of the Asplenium trichomanes group in the Czech Republic is presented. We detected diploid (2n = 72), tetraploid (2n = 144) and hybrid triploid plants (2n = 108). Based on the morphometric study, four intraspecific taxa are recognized. These taxa correspond to the four subspecies of A. trichomanes (A. t.subsp. trichomanes, <I.A. t. subsp. quadrivalens, A. t. subsp. pachyrachis and A. t. subsp. hastatum) distinguished in the floras of western, southern and northern Europe. Triploid plants were determined as A. t. nothosubsp. lusaticum (A. t. subsp. trichomanes × A. t. subsp. quadrivalens). The individual morphological characters used for determining subspecies are evaluated and a determination key presented.