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2. Five new species of Taraxacum sect. Ruderalia from Central Europe and Denmark
- Creator:
- Trávníček, Bohumil, Kirschner, Jan, and Štěpánek, Jan
- Type:
- article and TEXT
- Subject:
- Central Europe, Denmark, chorology, new species, sect. Ruderalia, Taraxacum, and taxonomy
- Language:
- English
- Description:
- 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.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
3. Sorbus omissa, a new endemic hybridogenous species from the lower Vltava river valley
- Creator:
- Velebil, Jiří
- Type:
- article, model:article, and TEXT
- Subject:
- chorology, Czech Republic, endemic, geographical distribution, hybridogenous epecies, karyology, Rosaceae, Sorbus latifolia agg., and taxonomy
- Language:
- English
- Description:
- Sorbus omissa is described as a new hybridogenous triploid (2n = 3x = 51) species belonging to the Sorbus latifolia group. This species is considered to be of hybrid origin, with S. danubialis and S. torminalis being its putative parental species. It is a stenoendemic whitebeam occurring in central Bohemia (Czech Republic) in the vicinity of the towns of Roztoky and Libčice nad Vltavou (Praha-západ district) in the valley of the lower Vltava river, where it grows primarily in oak forests (Viscario-Quercetum). The only two known populations contain approximately 150 individuals. This species differs from other similar Czech species of the S. latifolia group in having broadly elliptical to rhomboidal leaves with very shallowly lobed laminas, predominantly with 9–11 lateral leaf veins on each side, and is orange to orange-red fruit at maturity. Observation, morphological comparison and karyological (chromosome counts, DAPI flow cytometry) methods were used to identify this new species. A character-comparison table and a determination key including all taxa of the S. latifolia agg. endemic in the Czech Republic are provided. An illustration, a photograph and a distribution map of this new species are also presented.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Sorbus portae-bohemicae and Sorbus albensis, two new endemic apomictic species recognized based on a revision of Sorbus bohemica
- Creator:
- Lepší, Martin, Vít, Petr, Lepší, Petr, Boublík, Karel, and Kolář, Filip
- Type:
- article and TEXT
- Subject:
- apomixis, chorology, Czech Republic, endemic, hybridization, karyology, morphometrics, Rosaceae, Sorbus latifolia agg., SSR markers, and taxonomy
- Language:
- English
- Description:
- Two new apomictic triploid (2n = 3x = 51) species from the Sorbus latifolia group, S. portae-bohemicae M. Lepší, P. Lepší, P. Vít et K. Boublík and S. albensis M. Lepší, K. Boublík, P. Lepší et P. Vít, putative hybridogenous species originated from a cross between S. danubialis and S. torminalis, are distinguished and described based on a taxonomic and chorological revision of Sorbus bohemica (a hybridogenous triploid species from the same parental combination). A number of contemporary biosystematic techniques, including molecular (nuclear microsatellite markers), karyological (chromosome counts, DAPI flow cytometry) and multivariate and geometric morphometrics were used to assess the variation of the species and justify their independent taxonomic status. All three species occur sympatrically in the České středohoří Mts (NW Bohemia). Sorbus bohemica is recorded from 31 localities, based on a revision of herbarium vouchers and field research. Recent field studies failed to verify five of these localities. Sorbus portae-bohemicae is a stenoendemic in the Porta bohemica gorge (situated ca 7 km WNW of Litoměřice) where it grows in open oak forests (Luzulo-Quercetum and transition vegetation type to Melampyro nemorosi-Carpinetum) on ENE-facing slopes and rocks. The only known population of S. portae-bohemicae consists of 14 adult individuals. Sorbus albensis occurs at 12 localities W to NW of Litoměřice. The total number of individuals is estimated at 600. Most are in acidophilous oak forests (Luzulo-Quercetum and its mesic derivatives), scree forests (Aceri-Carpinetum) or shrubby slopes (Pruno-Ligustretum, Antherico-Coryletum). Populations of the new taxa show little genetic variation and are phenotypically homogenous and well separated from other Bohemian hybridogenous Sorbus species. A distribution map of the three species is provided. Photographs of the type specimens and in situ fructiferous individuals of the new species are presented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
5. Taxonomic revision of Hieracium nigrescens agg. in the Western Carpathians
- Creator:
- Chrtek jun., Jindřich and Mráz, Patrik
- Type:
- article and TEXT
- Subject:
- agamospermy, Carpathians, chorology, Compositae, Hieracium, Poland, Slovakia, and taxonomy
- Language:
- English
- Description:
- A taxonomic concept for the Hieracium nigrescens agg. (H. alpinum ≥ H. murorum) in the Western Carpathians is proposed. Three taxa at the species level are recognized, i.e. Hieracium jarzabczynum, H. mlinicae and H. vapenicanum. One new combination, Hieracium mlinicae (Hruby et Zahn) Chrtek f. et Mráz (H. nigrescens subsp. mlinicae Hruby et Zahn) is published. All taxa should be considered as endemic to the Western Carpathians (both the Polish and Slovakian parts). Detailed descriptions, drawings, lists of localities, distribution maps and determination key are provided along with a comparison with the last comprehensive account of the group (by Zahn 1936). Several lectotypes were chosen for the taxa recognized by Zahn within H. nigrescens s.l.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
6. taxonomic revision of the Pilosella alpicola group in the Carpathians
- Creator:
- Šingliarová, Barbora and Mráz, Patrik
- Type:
- article and TEXT
- Subject:
- chorology, chromosome number, distribution, Hieracium, flow cytometry, karyology, Poland, Romania, and Slovakia
- Language:
- English
- Description:
- A taxonomic study of the Pilosella alpicola group growing in the Carpathians revealed the presence of two morphologically distinguishable taxa: P. ullepitschii (Błocki) Szeląg and P. rhodopea (Griseb.) Szeląg. While P. ullepitschii is endemic to the Carpathians, P. rhodopea is a Balkan subendemic with two isolated localities in the Southern Carpathians (Mt Cozia and Mt Zmeuretu). The core area of distribution of P. ullepitchii is the natural subalpine and alpine meadows of the Western Carpathians (the Vysoké and Západné Tatry Mts in Slovakia and Poland). In addition, only three isolated localities are known from the Nemira Mts (Romanian Eastern Carpathians) and one from the Bucegi Mts (Romanian Southern Carpathians). Interestingly, the Romanian populations occur in man-made habitats (secondary pastures). Karyological and flow cytometric analyses of 305 plants from 13 populations of P. ullepitschii revealed only diploid plants (2n = 2x = 18). One Carpathian population of P. rhodopea from Mt Cozia is also diploid. This is the first report of diploidy in this species. However, the populations from the main part of the distribution of this taxon in the Balkan mountains include other cytotypes. Detailed morphological descriptions and distributions for both taxa are given.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
7. Taxonomy of Rubus ser. Discolores in teh Czech Republic and adjacent regions
- Creator:
- Trávníček, Bohumil and Zázvorka, Jiří
- Type:
- article and TEXT
- Subject:
- Central Europe, Czech Republic, chorology, Rosaceae, Rubus, ser. Discolores, and taxonomy
- Language:
- English
- Description:
- The current state of the taxonomy of Rubus ser. Discolores in the Czech Republic is summarized. Since 1995, when the group was treated in the Flora of the Czech Republic (Holub 1995), six new species have been recognized, some of which are also known from adjacent areas. They are described in the present study: R. austroslovacus Trávníček, R. flos-amygdalae Trávníček et Holub, R. guttiferus Trávníček et Holub, R. parthenocissus Trávníček et Holub, R. pericrispatus Holub et Trávníček and R. portae-moravicae Holub et Trávníček. The first five belong to the group of triploid species close to R. montanus Lej. and R. grabowskii Weihe, whilst R. portae-moravicae is related to R. praecox Bertol. Two additional species, originally recognized under provisional names, were found to be identical to species described earlier: R. perperus H. E. Weber and R. phyllostachys P. J. Mueller; the latter is also found in Slovakia. At present, 17 indigenous species, one naturalized alien (R. armeniacus Focke) and one rare garden escape (R. ulmifolius Schott) of the ser. Discolores are known to occur in the Czech Republic. Distribution data and a key for the identification of all the species are presented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/