Additions to the flora of the Czech Republic. XIII.

This thirteenth part of floristic contributions includes newly published data of critically endangered species and data unpublished so far. The species Carex×moravica and Sorbus pauca described from the Czech Republic as new to science, data of taxa newly discovered on the territory of the Czech Republic (Callitriche ×vigens, Pilosella fusca, P. norrliniformis and Verbascum ×duernsteinense) and data of alien species found in the Czech Republic for the first time (Geranium aequale, G. thunbergii, Panicum virgatum) are summarized. Also the recently found Sagina apetala, previously considered to be extinct from the Czech Republic, is included. Furthermore, criticaly endangered species (according to the Red List of Vascular Plants of the Czech Republic) are reported from new sites (e. g. Anacamptis pyramidalis, Botrychium matricariifolium, B. multifidum, Centunculus minimus, Chenopodium chenopodioides,Ch. urbicum, Conringia orientalis, Crepis setosa, Dactylorhiza incarnata, Echium maculatum, Epipactis moravica, E. pontica, Epipogium aphyllum,Eriophorum gracile, Filago vulgaris, Gentianella amarella, Geranium divaricatum, Juncus capitatus, Limodorum abortivum, Lindernia procumbens, Listera cordata, Lycopodiella inundata, Malaxis monophyllos, Marrubium peregrinum, Moneses uniflora, Nuphar pumila, Ophrys apifera, Orchis morio, Phyllitis scolopendrium, Plantago maritima subsp. ciliata, Pulicaria vulgaris and Typha shuttleworthii). Finally, less rare and threatened species are reported from areas where they had not been recorded yet (Asperula cynanchica, Chenopodium vulvaria, Coronopus didymus, Epipactis atrorubens, Lithospermum officinale, Monotropa hypophegea, Parietaria officinalis, Pyrola rotundifolia, Ranunculus arvensis and Viola rupestris).