A taxonomic revision of Taraxacum sect. Leucantha Soest is presented. Species in this section are mainly characterized by the pale bordered and appressed outer involucral bracts, achenes covered with subsparse coarse spinules, thick cylindrical cone and a relatively short, thicker rostrum, and often white or pale yellowish flowers. They occur in subsaline wet meadows and steppe depressions over a large area including Mongolia, South Siberia, NE, N and W China, Tibet, the Western Himalayas, Tadzhikistan, Kyrgyzstan and E and NE Kazakhstan. Eighteen species are recognized, seven of them described as new: Taraxacum niveum from the Altai and Dzhungaria, T. candidatum centred in Ladakh, Tadzhikistan and Kyrgyzstan, T. album from Kyrgyzstan, T. flavidum from Mongolia and Transbaikalia, T. occultum from East Mongolia, T. virgineum from Ladakh, India, and T. inimitabile from Gobi-Altai, Mongolia. An analysis of syntypes of the names T. dealbatum Hand.-Mazz. and T. sinense Dahlstedt is given. For the safe interpretation of the name T. luridum, epitype was designated. All the species are agamospermous but sexuality and diploidy is documented for a few Transbaikalian plants of the section Leucantha.
On the basis of rich material from Asia, a recently described group of dandelions, Taraxacum sect. Stenoloba Kirschner et Štěpánek, is revised taxonomically. Four previously described species are recognized: T. sinomongolicum, newly typified, T. mongoliforme, with a lectotype replacing the original holotype now not extant, and a new epitype, T. scariosum, a new combination of Leontodon scariosus Tausch, replacing the frequently confused names, T. asiaticum, newly typified, and T. stenolobum, and T. multisectum, a taxon for the first time compared with other members of the section. Three new species are described: T. abax occupies a large range from S Siberia and Mongolia to NE China, T. abalienatum and T. odibile are known from Mongolia and SE Siberia. Taraxacum abax and T. abalienatum represent core species of the section Stenoloba, whilst T. odibile exhibits a mixture of characters of sections Stenoloba and Leucantha. All the known members of the section Stenoloba are agamosperms. Taraxacum mongoliforme, T. abax and T. scariosum proved to be triploid with 2n = 24. This account includes detailed descriptions and an identification key.
On the basis of the authors’ collections and cultivated material from Asia, a recently described group of dandelions, Taraxacum sect. Suavia, is revised. In addition to three species described previously (T. haneltii, T. sumneviczii and T. formosissimum), six new species from Mongolia and Kyrgyzstan are recognized. Three of them, T. suave, T. stupendum and T. margaritarium, possess most of the features characterizing the section Suavia, one, T. suasorium, is regarded as intermediate between sections Suavia and Leucantha, whilst the remaining two, T. nobile and T. venustius, exhibit some characters of another related section (T. sect. Stenoloba). The members of the section Suavia are agamospermous. Detailed descriptions, drawings and an identification key are given.
A detailed study of Taraxacum sect. Ruderalia for the 8th volume of the Flora of the Czech Republic revealed five new agamospermous species, viz. T. atroviride Štěpánek et Trávníček, T. clarum Kirschner, Štěpánek et Trávníček, T. moldavicum Chán, H. Ollgaard, Štěpánek, Trávníček et Žíla, T. urbicola Kirschner, Štěpánek et Trávníček and T. violaceifrons Trávníček. These species are formally described, thoroughly characterized morphologically and compared with similar taxa. They are known from numerous localities in Central Europe; T. moldavicum, in addition to the Central European distribution, is known to occur in two regions in Denmark. All these species are also documented by photographs of their general habit and important features.
Plant names based on the original material from a restricted region are scientifically important for the study of local biodiversity. Names typified with or entirely based on the original material from the Czech Republic are studied in the present paper; the names are confined to cases of generally accepted names published and taxa described in the period 1753–1820. Some names with original material coming from a border region (mostly near the Polish border) are included, too. Brief notes and references are given to introduce the authors of names and the history of their herbarium collections. New data are given on publications and herbaria of F.W. Schmidt, T. Haenke and J. E. Pohl, including examples of their handwritings; the other authors being C. Linnaeus (and J. Burser), J. Zauschner, K. L.Willdenow, J. C. Mikan, K. Sternberg, H. A. Schrader, L. Trattinick, K. B. Presl, J. S. Presl, P. M. Opiz, I. F. Tausch and H. G. L. Reichenbach. Nomenclatural and taxonomic notes are given on Aconitum plicatum, Allium senescens subsp. montanum, Gagea bohemica, Plantago uliginosa, Spergularia salina, Valeriana officinalis, V. exaltata, V. sambucifolia and Veronica triloba. A number of names are typified (lecto-, neo- , epitypes): Allium montanum, Athyrium distentifolium, Erysimum arcuatum (= Barbarea vulgaris subsp. arcuata), Schmidtia (= Coleanthus) subtilis, Epilobium nutans, Ornithogalum bohemicum (= Gagea bohemica), Hieracium sudeticum, Myosotis sparsiflora, Cynoglossum (= Omphalodes) scorpioides, Pedicularis sudetica, Phyteuma nigrum, Plantago uliginosa (with an identification key), Poa laxa, Soldanella montana, Symphytum bohemicum, Thlaspi caerulescens, Valeriana exaltata (with notes on the typification of V. officinalis), V. sambucifolia, Veronica triloba (with a note on the status of names in Čelakovský‘s works), Viola sudetica and V. saxatilis. The other names included in the list are Avenula planiculmis, Cardamine amara subsp. opicii, Eriophorum vaginatum, Hieracium rupestre (= H. schmidtii), Luzula sudetica, Mentha longifolia, Potentilla lindackeri, Rosa elliptica, Salix silesiaca, Stipa capillata and Viola rupestris. A few cases of names excluded from the list are also analysed: Achillea millefolium subsp. sudetica, Alchemilla fissa, Carex bohemica, Dactylorhiza longebracteata, Gagea pusilla, Geranium bohemicum, Matricaria recutita, Veronica dentata, Spergularia salina (correct name: S. marina), Gentianella obtusifolia, Myosotis alpestris and Mentha rotundifolia. For most cases, conservation status and situation at the original localities (in many cases in protected areas) are discussed.
A long-standing problem with the taxonomic status and synonymy of the names Taraxacum nigricans (Kit.) Reichenb. and T. alpestre (Tausch) DC. is resolved. These two names, the oldest ones referable to high mountain dandelions in Central Europe, are typified, and a detailed comparison of these species’ morphology, genotype make-up, karyotypes and distribution is provided, together with a discussion of other cases of similar and probably closely related agamospermous taxa of Taraxacum and Hieracium. Taraxacum nigricans (2n = 32) and T. alpestre (2n = 32) are endemic to the Nízke Tatry Mts, Slovakia, and the Krkonoše/Karkonosze Mts, Czech Republic/ Poland, respectively. These are shown to differ in a series of minor but constant morphological, allozyme and karyotype features, and their treatment as separate agamospermous species is supported. A detailed analysis of cultivated and wild material from the Carpathians revealed the existence of a sexual taxon very close to the above two species and endemic to the region of the Bucegi Mts, Romania. It is described as a new species, T. carpaticum Štěpánek et Kirschner. Two new agamospermous species, apparently allied to T. nigricans, are described: T. rupicaprae Štěpánek et Kirschner, a species characterized by orange-ochraceous achenes and confined to the High Tatra Mts, and T. elegantissimum Štěpánek et Kirschner (2n = 24), which has substantially broader outer bracts and is known from the Rodna, Retezat and Fagaras Mts, Romania. Another three species are described that are morphological similar to T. carpaticum: T. pastorum (the Fagaras Mts, Romania), T. iucundum (the Retezat Mts, Romania) and T. pseudoalpestre (the Fagaras Mts, Romania).
Two new species, Taraxacum maricum and Taraxacum cristatum, of the section Erythrosperma from Central Europe are described in this paper. These species are similar to western European taxa, T. maricum to T. proximum, and T. cristatum is morphologically close to T. scanicum. Both new taxa are triploid apomictic microspecies. Specific characteristics, information on distribution and ecology and comparison with similar species are presented. Pictures and distribution maps of the new species are also included.