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| Rubus violaceifrons P. Havlíček, Trávn. & Velebil, in Havlíček, Trávníček & Velebil, 2022. |
Abstract
Rubus violaceifrons, a new species from central and north-eastern Bohemia (Czech Republic) is described and illustrated, and its distribution is characterized in detail. We classify it as a member of the series Pallidi of the subgenus Rubus, section Rubus and subsection Hiemales, although its weak specimens partly resemble R. guentheri from ser. Glandulosi. Like all species of R. ser. Pallidi studied so far, R. violaceifrons is tetraploid, as determined using flow cytometry. A detailed morphological comparison of the new bramble species with similar taxa is presented. A determination key including all taxa of the R. ser. Pallidi occurring in the Czech Republic is provided.
Key words: apomictic taxa, batology, ploidy level, taxonomy
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| Rubus violaceifrons: a: section of primocane stem with leaf; b: detail of primocane stem indumentum; c: detail of terminal leaflet margin; d: infructescence; e: detail of section of inflorescence axis; f: detail of section of peduncle; g: flower; h: carpel. Scale bars 1 cm, short – a, d; middle – b–c, e–g; long – h. Del. A. Skoumalová. |
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| Rubus violaceifrons: A: flowers; B: inflorescence; C: primocane stem with basal part of leaf petiole; D: detail of gynoecium; E: detail of part of inflorescence; F: 4-foliolate primocane leaf; G: 5-foliolate primocane leaf. Photos J. Velebil. |
Rubus violaceifrons P. Havlíček, Trávn. & Velebil, sp. nov.
Ecology:—Rubus violaceifrons most often grows in margins, clearings and openings of coniferous and mixed woodlands and forest plantations, usually in somewhat shaded places. It is clearly a nemophilous bramble species according to the concept of Weber (1995: 296). It is usually found on permeable, moderately humid to slightly dry soils that neutral to slightly acidic. The elevation range of the species spans from 175 m a.s.l. (Káraný and Nový Vestec villages) to 590 m a.s.l (Otradovice village).
Distribution:—According to the concept of Weber (1996), Rubus violaceifrons is a “regional” bramble species: the longest diameter of its distribution area is about 150 km (Fig. 4). Currently, it is known from 42 localities dispersed in central and eastern Bohemia in the Czech Republic. The species is possibly an endemic taxon of the country, but it could be found also in southern Poland (particularly in the Kłodzko County or in Silesia). In terms of the grid system of the Atlas Florae Europaeae (for the genus Rubus, see Kurtto et al. 2010), R. violaceifrons is present in the following units: 33UWS4, 33UVR1, 33UVR3, 33UVR4, 33UVQ3, 33UWR1, 33UWR2, 33UWR3, 33UWR4.
Etymology:—The epithet “violaceifrons” is a reference to the intense colouration of stem parts and their stalked glands, as well as to the very conspicuous red-violet colour of styles in open flowers.
Petr Havlíček, Bohumil Trávníček, Jiri Velebil. 2022. Rubus violaceifrons (Rosaceae), A New Bramble Species from Bohemia (Central Europe, Czech Republic). Phytotaxa. 568(3); 241-254. DOI: 10.11646/phytotaxa.568.3.1
