New Literature

Literature Archive: 2016 | 2017 | 2018 | 2019 | 2020

Not all members of the International Cichorieae Network do have access to botanical libraries. As a service we would like to point to recent publications regarding Cichorieae. However, some articles will escape our attention. Therefore, your hints to recent publications are always welcome. 

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18 September 2020

Kirschner J., Štěpánek J., Klimeš L., Dvorský M., Brůna J., Macek M. & Kopecký M. 2020: The Taraxacum Flora of Ladakh, with notes on the adjacent regions of the West Himalaya. – Phytotaxa 457: 1-409.

Abstract
“Ladakh (Jammu & Kashmir State, NW. India) is a region in the Trans-Himalaya between the Great Himalayan Range in the south and the eastern Karakoram in the north, at the southwestern edge of the Tibetan Plateau. Its flora, vegetation, ecology and climatic conditions were thoroughly studied by the late Leoš Klimeš. As regards the genus Taraxacum (Compositae-Crepidinae), Ladakh was an almost unexplored area. L. Klimeš accumulated an ample material (50 Ladakh species are exclusively based on his material), either as field samples or as cultivated specimens; together with further recent collections of other collectors, cultivated by JK & JŠ, and the historical herbarium material, it forms a basis for the present monograph. It presents a taxonomic treatment of all Taraxacum species documented from Ladakh, including notes on ecology and distribution, and notes on dandelions from adjacent regions, mainly Gilgit-Baltistan, Spiti, Lahaul and the cis-Himalayan Kashmir. Each species is characterized by a full description, photographs of involucre, capitulum and achenes, whenever available; species are arranged systematically in sections, the latter also with descriptions and identification keys including all the taxa from Ladakh and adjacent areas. Treatments of five sections include all or almost all of their members. Distribution maps and a complete list of specimens studied are given for all Ladakh dandelions. A comprehensive introduction in the vegetation of Ladakh, general features of the genus Taraxacum and the history of its exploration are also provided. As regards the Taraxacum diversity, the broader region covered by the present monograph includes representatives of one third of the world sectional diversity. One hundred and twenty one taxa, belonging to 19 sections, are given a full treatment in the monograph, including those from adjacent regions (the latter, 46 species, also with full descriptions and illustrations); the Ladakh proper harbours 76 taxa in 17 sections, one of which is described as new. Fifty one taxa are described as new for science, 42 from Ladakh, 9 from other regions. For all species, the mode of reproduction is given (mostly inferred from indirect indicators). Only seven species were found at least partly sexual (five of them outside the limits of the Ladakh proper); all the other taxa exhibit agamospermy. Ladakh and adjacent regions of Pakistan and India rank among the regions with the highest sectional and morphological Taraxacum diversities."

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25 August 2020

Behçet L. & Yapar Y. 2020: Lactuca anatolica (Asteraceae: Lactucinae), a new species from eastern Anatolia (Turkey). – Phytotaxa 455: 287-294.

Abstract
Lactuca anatolica is described as a new species from the province of Bingöl, and is known from only one locality. Its diagnostic characters are discussed, and taxonomic comments are presented. Lactuca anatolica is similar to L. leucoclada, L. orientalis subsp. nuristanica and L. orientalis subsp. orientalis but differs from these species in achenes, indumentum and leaves. Its achenes were investigated using scanning electron microscopy (SEM). Data on ecology and IUCN conservation status of the new species are also presented. A distribution map of the new and related species is provided."

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8 July 2020

Dudáš M., Šuvada R., Majeský Ľ. & Vašut R. J. 2020: Taraxacum sect. Erythrosperma in Slovakia. Part II. Notes on distribution and ecology of Taraxacum danubium. – Thaiszia 30: 81-92.

Abstract
Taraxacum danubium is xerothermic species of Taraxacum sect. Erythrosperma occurring in Central Europe with the highest frequency in southeastern Czechia, northeastern Austria and southwestern Slovakia. Since its description in 1970 from Devínska Kobyla Hills in Slovakia the species was documented from numerous localities across the country, however overall study on the species distribution in Slovakia was still lacking. Thus in this paper, we present a detailed survey on its chorology in Slovakia based on our long-term field observation and data excerption from herbarium specimens with commentary on the distribution (over 60 localities in Slovakia) and biology of the species. Western Slovakia seems to be a centre of its distribution, while towards east the number of populations rapidly decreases. Karyology and ecology are discussed. The full list of locations and distribution map are presented."

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8 July 2020

Richards A. J. 2020: Taraxacum section Erythrosperma. – In: Rich T. C. G. & Jermy A. C. (ed.), Plant crib, ed. 3. – London: Botanical Society of the British Isles. Available at https://bsbi.org/plant-crib, accessed July 2020

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8 July 2020

Richards A. J. 2020: Taraxacum section Naevosa. – In: Rich T. C. G. & Jermy A. C. (ed.), Plant crib, ed. 3. – London: Botanical Society of the British Isles. Available at https://bsbi.org/plant-crib, accessed July 2020.

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8 July 2020

Rich T. C. G. 2020: Hieracium lanceolatum (Asteraceae) does not occur in Britain. – Brit. & Irish Bot. 2: 133-143.

Abstract
“The status of Hieracium lanceolatum Vill. in Britain has been reviewed against the original descriptions and material from the western Alps. British plants named as H. lanceolatum show a poor match with H. lanceolatum and fit H. prenanthoides Vill. better. It is concluded that H. lanceolatum does not occur in Britain."

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8 July 2020

Rich T. C. G. 2020: The current status of the rare Scottish endemic Hieracium drummondii Drummond’s hawkweed (Asteraceae). – Brit. & Irish Bot. 2: 127-132.

Abstract
“The records of Hieracium drummondii Pugsley, Drummond’s hawkweed, (Asteraceae) are reviewed. It has been recorded from eight general localities and it not accepted in four others. Seven of the eight localities have been visited but only one population of 20-25 plants was found at Crinan. It is IUCN Threat Category ‘Critically Endangered’ and is on the verge of extinction."

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8 July 2020

Day J. J. & Richards A. J. 2020: Taraxacum pseudomarklundii, a south-western European species, native in South Devon (v.c.3). – Brit. & Irish Bot. 2: 73-76.

Abstract
“An enigmatic dandelion first collected in the UK in 2014 from a lanebank on Dartmoor (v.c.3) has been determined as Taraxacum pseudomarklandii (Soest), previously only known from north-west Spain and south-west France, an unusual biogeographic alliance in our Taraxacum-flora. It is triploid (2n = 24). This taxon has now been confirmed from several locations in South Devon and one site in Ireland (Meath, v.c.H22)."

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8 July 2020

Rich T. C. G. 2020: Lectotypification and neotypification of some names in British Hieracium section Foliosa (Asteraceae). – Brit. & Irish Bot. 2: 69-72.

Abstract
“Types are designated for 11 names in Hieracium section Foliosa (Fr.) Arv.-Touv. (Asteraceae). Lectotypes are designated for Hieracium aestivum subsp. subumbellatiforme Zahn, Hieracium corymbosum Fr. var. pycnotrichum W. R. Linton, Hieracium crocatum Fr. var. maritimum F. Hanb., Hieracium latobrigorum forma angustifolium Pugsley, Hieracium obesifolium Pugsley, Hieracium pseudamplidentatum var. stenophyllum Pugsley, Hieracium rigidum var. tavense Ley, Hieracium strictum var. amplidentatum F. Hanb. and Hieracium strictum var. subcrocatum E. F. Linton. Neotypes are designated for Hieracium inuloides subsp. strictiforme Zahn and Hieracium neocorymbosum var. crocatiforme Pugsley."

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8 July 2020

McCosh D. J., Barlow D., Burrow B. & Rich T. C. G. 2020: Three new species of Hieracium (Asteraceae) from northern England. – Brit. & Irish Bot. 2: 56-63.

Abstract
“Three new species of hawkweed are described in Hieracium section Stelligera from Northern England, based on the herbarium collection of Vincent Jones; Hieracium lacinifolium V. Jones, Hieracium obovatifolium V. Jones and Hieracium pseudosubcyaneum V. Jones."

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8 July 2020

Richards A. J. 2019: Five new species of Taraxacum section Celtica (Asteraceae) from North-west Europe. – Brit. & Irish Bot. 1: 167-184.

Abstract
“Five new species of the mostly west European Taraxacum section Celtica A.J.Richards (Asteraceae) are described.  Taraxacum amicorum is only known from Somerset, England; T. atrocollinum has also been found in Devon and Ireland. Taraxacum chrysoglossum is described from Bute and is also recorded from the eastern Highlands, Scotland. Taraxacum elegantifrons occurs on light calcareous soils in Ireland. Taraxacum chlorofrugale P. Oosterv. ex A.J. Richards from Germany, Netherlands, south England and Ireland is described formally for the first time."

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8 July 2020

Crouch H. J., McDonnell E. J., Miles S. & Rich T. C. G. 2019: Distribution and population size of Hieracium stenolepiforme, Cheddar Hawkweed (Asteraceae).  – Brit. & Irish Bot. 1: 1-6.

Abstract
“The distribution and population size of Hieracium stenolepiforme (Pugsley) P. D. Sell & C. West, Cheddar Hawkweed (Asteraceae) has been assessed. It is endemic to Cheddar Gorge and the adjacent Black Rock Nature Reserve, Somerset, England (vice-county 6, North Somerset). Historical records show that it has been recorded in Cheddar Gorge and at Black Rock but has declined.  On 11 June 2000, 52 plants were counted in the main gorge and 5 plants at Black Rock; on 14 June 2016, 59 plants were recorded in Cheddar Gorge but none at Black Rock.  Hieracium stenolepiforme is IUCN (2001) threat status ‘Critically Endangered’."

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23 June 2020

Qiu J., Zhang J.-W., Gao T.-G. & Tan D.-Y. 2020: Crepis desertorum (Asteraceae, Cichorieae), a new species from northern Xinjiang (China) based on morphological and molecular data. – Pl. Diversity  42: 74–82.

Abstract
Crepis desertorum from the Junggar Basin of northern Xinjiang, northwestern China, is described as a new species. Molecular studies indicate that the species is closely related to Crepis frigida. Morphological studies indicate that it is similar to Crepis sancta subsp. bifida but differs from the latter taxon in having glandular hairs on the stem, a flat receptacle and dimorphic achenes. Chromosome features and pollen and achene ultrastructure also are described for the new species."

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23 June 2020

Hanselmann D. 2019: Crepis sancta (L.) Bornm. - „wieder neu" für Deutschland. – Mainzer Naturwiss. Archiv 56: 171–186.

Abstract
“Since the 1800s, the Holy Hawksbeard, Crepis sancta(L.) BoRNM., native to the Middle East and neighboring regions, has spread to !arge parts of Western Europe. In Germany however, the latest records date to the l 940s. With the discovery of a !arge and thriving population in the city of Worms in 2017, this species may get a second chance to establish itself as a permanent member of the German flora."

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14 June 2020

Marciniuk J., Marciniuk P. & Wolanin M. M. 2020: [New records of Taraxacum from Ukraine] in Nobis M. & al., Contribution to the flora of Asian and European countries: new national and regional vascular plant records, 9. – Turk. J. Bot. 44, https://dx.doi.org/10.3906/bot-1908-41

Abstract
“The paper presents new records for ... Taraxacum acervatulum, T. aequilobum, T. amplum, T. ancistrolobum, T. bellicum, T. collarispinulosum, T. copidophyllum, T. corynodes,T. dentatum, T. gelertii, T. infuscatum, T. ingens, T. lucidum, T. paucilobum, T. plumbeum, T. portentosum, T. sinuatum, T. subhuelphersianum, T. telmatophilum, T. undulatiforme and T. undulatum (Asteraceae) from Ukraine ..."

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14 June 2020

Coşkunçelebı K., Gültepe M., Güzel M. E. & Makbul S. 2020: Tragopogon abbreviatus (Asteraceae): a little-known species inferred from morphological and molecular analysis. – Turk. J. Bot. 44: 269-280.

Abstract
Tragopogon  porrifolius  occurs  in  Turkey  with  3  taxonomically  confused  subspecies:   T.  porrifolius  subsp.  eriospermusT.  porrifolius subsp.  longirostris, and  T.  porrifolius  subsp.  abbreviatus.  In  the  present  paper,  T.  porrifolius  subsp.  abbreviatus endemic  to  Turkey  is  raised  at  specific  level  based  on  morphological  and  molecular  analysis.  After  detailed  assessment  of  original  herbarium  specimens and literature studies, we found that this name is not typified yet. Thus, a lectotype is provided together with an emended diagnosis; synonym, distribution map, and conservation status for the first time. Additionally, a preliminary phylogenetic position of this little-known taxon is given on several newly sequenced data.”

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2 June 2020

Steinbach P. 2019: Zur Reaktion des Lämmersalats Arnoseris minima (L.) Schweigg. & Körte auf Frost und Schnee. – Bot. Rundbrief Mecklenburg-Vorpommern 56: 66-70.

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2 June 2020

Gottschlich G. 2020: Anmerkungen zur Nomenklatur von Hieracium kalksburgense Wiesb. und Wiedereinsetzung des Namens Hieracium canum Peter. – Kochia 13: 17–21.

Abstract
“The type material of Hieracium kalksburgense is heterogeneous and does not fit with the taxonomical amplitude hitherto ascribed to this intermediate species. According to the intention of Wíesbaur as author the name H. kalksburgense is lectotypífied with a specimen, belonging to H. acutifolium, and thereby synonymized. As a  consequence, the name H. canum Peter is re-established for the intermediate species „cymosum < pilosella" and lectotypífied. As there exists no valid name in the alternative genus concept under Pilosella, a new combination is provided.”

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10 April 2020

Szeląg Z. 2020: Hieracium richianum (Asteraceae), a new species of H. sect. Alpina from the Eastern Carpathians in Romania. – Phytotaxa 436: 93-96.

Abstract
Hieracium richianum, a new, apomictic, tetraploid (x = 9) species is described from the Ciucaș Mountains, Eastern Carpathians, Romania. It belongs to the H. fritzei aggregate comprising taxa of presumably hybrid origin between H. alpinum and H. prenanthoides. The new species is illustrated with photos of the holotype and living plants.”

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7 April 2020

Bartolucci F., Galasso G. & Conti F. 2020: Nomenclatural novelties and typification of names in Scorzonera sensu lato (Asteraceae, Cichorieae) for the Italian vascular flora. – Phytotaxa 437: 279-290.

Abstract
“According to recent molecular study, the genus Scorzonera sensu lato is polyphyletic. A revised circumscription of this genus was proposed with the recognition of seven genera: Scorzonera sensu stricto, Gelasia, Lipschitzia, Pseudopodospermum, Pterachaenia, Ramaliella, and Takhtajaniantha. Accordingly, a taxonomic treatment of the genus Scorzonera sensu lato for the Italian vascular flora is presented. Nomenclatural types for six names are designated here: Scorzonera calcitrapifolia var. decumbens, S. columnae, S. deliciosa, S. neapolitana, S. trachysperma var. undulata, and S. villosa. Furthermore, the following new combinations are proposed: Gelasia villosa subsp. columnae, Pseudopodospermum hispanicum subsp. asphodeloides, P. hispanicum subsp. neapolitanum, and P. undulatum subsp. deliciosum.”

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7 April 2020

Müller C. M., Linke B., Strickert M., Ziv Y., Giladi I. & Gemeinholzer B. 2019: Comparative genomic analysis of three co-occurring annual Asteraceae along micro-geographic fragmentation scenarios. – Perspectives Pl. Ecol. Evol. Syst. 42: 125486.

Abstract
“This is the first population genomic analysis that examines micro-evolutionary changes in co-occurring plant species, in fragmented habitats, along a precipitation gradient. We applied Genotype-by-Sequencing (GBS) on three different annual Asteraceae on the same sites that share similar life history strategies, but different pollination and dispersal strategies (Catananche lutea, Geropogon hybridus, Urospermum picroides).

We tested if the genetic diversity for all species correlates with effective population sizes along the precipitation gradient and whether therefore genetic drift drives evolution at range edges. However, our results support this hypothesis for only one species (C. lutea) but refute it for the other two. Potential genomic signals of adaptation to the high precipitation gradient were found only in one species (U. picroides). We also tested if species with complex pollination and diversified dispersal strategies are less affected by small scale habitat fragmentation, but the opposite is true. Biological differences between the species studied (pollination and dispersal) explain population genetic differences along the precipitation gradient at range edges rather than environmental filters. Pairwise correlation analyses showed no or only weak similarities in the accumulation of mutations in the different species.

Our results suggest that the processes driving evolution in different co-occurring species are different, so that most genomic similarities in our investigations may only represent temporary stages in evolution.”

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12 March 2020

Wang Z.-H., Kilian N., Chen Y.-P. & Peng H. 2020: Sinoseris (Crepidinae, Cichorieae, Asteraceae), a new genus of three species endemic to China, one of them new to science. – Willdenowia 50: 91–110.

Abstract
“Studies to elucidate the systematic position of two Chinese species described originally as Lactuca hirsuta and L. scandens, of which only historical specimens from the late 19th and early 20th centuries were known, revealed the occurrence of three different species. Molecular phylogenetic analysis of these species based on sequences of the nuclear ribosomal internal transcribed spacer (nrITS) region and three plastid DNA markers (trnL-F, psbA-trnH, matK) uncovered a hitherto unknown lineage in a first comprehensive phylogenetic backbone of the subtribe Crepidinae (Asteraceae, tribe Cichorieae). Substantiated by comparative morphological studies, this lineage is described as a new genus, named Sinoseris, endemic to the Chinese provinces Sichuan and Yunnan. One of its three species is new to science, while another is conspecific with both L. hirsuta and L. scandens. The third was meanwhile described by other authors as Nabalus muliensis and is now transferred to Sinoseris.”

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12 March 2020

Hatami E., Mirtadzadini M., Bordbar F. & Jones K. E. 2020: Delimitation of Iranian species of Scorzonera subg. Podospermum and S. subg. Pseudopodospermum (Asteraceae, Cichorieae) based on morphological and molecular data. – Willdenowia 50: 39–63.

Abstract
Scorzonera L. is represented by 57 species in Iran including three subgenera: S. subg. Scorzonera, S. subg. Podospermum and S. subg. Pseudopodospermum. Species of S. subg. Podospermum and S. subg. Pseudopodospermum in Iran are morphologically similar, which limits species delimitation. In order to clarify intersubgeneric and interspecific delimitation in Iran, we carried out extensive sampling of the two subgenera in Iran. We conducted phylogenetic analyses based on the nuclear Internal Transcribed Spacer (nrITS), detailed morphological studies, and we evaluated the systematic value of achene features. Our results showed that Scorzonera s.l. is polyphyletic, and both S. subg. Podospermum and S. subg. Pseudopodospermum are monophyletic. The monophyly of S. subg. Podospermum morphologically corresponds to a combination of characters containing pinnatifid leaves, phyllaries with black corniculate projections, and the presence of a swollen carpopodium on the achenes. A comparison of the topology observed in the nrITS phylogeny with achene features indicates that a sculptured achene wall surface in members of S. subg. Pseudopodospermum provides a synapomorphy for this lineage. This study supports a broader circumscription of S. subg. Pseudopodospermum with the addition of S. calyculata (S. sect. Incisae), S. ovata, S. papposa and S. paradoxa (S. sect. Papposae). Finally, we provide a taxonomic treatment, including an identification key and species diagnoses and distributions, with nomenclature of Iranian species.”

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12 March 2020

Brandstätter G. 2019: Hieracium rotundatum Kit. ex Schult. neu für die Flora Deutschlands und Tschechiens. – Stapfia 111: 92-96.

Abstract
“Presentation and discussion of the first records of Hieracium rotundatum for the flora of Germany and the Czech Republic.”

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12 March 2020

Szeląg Z. & Vladimirov V. 2020: Pilosella bulgarica (Asteraceae) a new hybridogenous species from Bulgaria. – Phytotaxa 428: 290–294.

Abstract
“The newly described Pilosella bulgarica combines the morphological features of P. pavichii and P. rhodopea, and grows in the subalpine habitats in the Kurudere gorge in the Triglav massif, Central Stara Planina Mountains, Bulgaria. It is illustrated with photos of the holotype (kept at SOM) and living plants in the locus classicus.”

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15 January 2020

Gottschlich G. 2020: Synopse der für Deutschland nachgewiesenen Arten und Unterarten der Gattung Hieracium s.l. (Hieracium s. str. und Pilosella), aufgeschlüsselt nach Vorkommen in den einzelnen Bundesländern / Synopsis of all species and subspecies of the genus Hieracium s. l. (Hieracium s. str. and Pilosella) in Germany according to the records cited in literature for the German federal states. – Forum Geobot. 9: 1–59.

Abstract
“A list of 205 collective species and 1563 subspecies of the genus Hieracium s. l. detected for Germany and its federal states, is provided. As the most infraspecific taxa were described under Hieracium s.l. and to avoid too much invalid names under Pilosella in the list, a separation of Hieracium and Pilosella is remained undone. By coloured marking additional informations are given whether a subspecies is originally described from a German federal state or its name has a syntype from Germany.”

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15 January 2020

Van Es J & Tison J.-M. 2018: Notices descriptives de Hieracium des Alpes françaises. – Conservatoire Botanique National Alpin, 255 p. http://www.cbn-alpin-biblio.fr/GED_CBNA/113330293151/BB_33694.pdf

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9 January 2020

Zaika M. A., Kilian N., Jones K., Krinitsina A. A., Nilova M. V., Speranskaya A. S. & Sukhorukov A. P. 2020: Scorzonera sensu lato (Asteraceae, Cichorieae) – taxonomic reassessment in the light of new molecular phylogenetic and carpological analyses. – PhytoKeys 137: 1-85.

Abstract
Scorzonera comprises 180–190 species and belongs to the subtribe Scorzonerinae. Its circumscription has long been the subject of debate and available molecular phylogenetic analyses affirmed the polyphyly of Scorzonera in its wide sense. We provide a re-evaluation of Scorzonera and other related genera, based on carpological (including anatomical) and extended molecular phylogenetic analyses. We present, for the first time, a comprehensive sampling, including Scorzonera in its widest sense and all other genera recognised in the Scorzonerinae. We conducted phylogenetic analyses using Maximum Parsimony, Maximum Likelihood and Bayesian analyses, based on sequences of the nuclear ribosomal ITS and of two plastid markers (partial rbcL and matK) and Maximum Parsimony for reconstructing the carpological character states at ancestral nodes. Achene characters, especially related to pericarp anatomy, such as general topography of the tissue types, disposition of the mechanical tissue and direction of its fibres, presence or absence of air cavities, provide, in certain cases, support for the phylogenetic lineages revealed. Confirming the polyphyly of Scorzonera, we propose a revised classification of the subtribe, accepting the genera Scorzonera (including four major clades: Scorzonera s. str., S. purpurea, S. albicaulis and Podospermum), Gelasia, Lipschitzia gen. nov. (for the Scorzonera divaricata clade), Pseudopodospermum, Pterachaenia (also including Scorzonera codringtonii), Ramaliella gen. nov. (for the S. polyclada clade) and Takhtajaniantha. A key to the revised genera and a characterisation of the genera and major clades are provided.”

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7 January 2020

Mráz P., Filipaş L., Bărbos M. I., Kadlecová J., Paštová L., Belyayev A. & Fehrer J. 2019: An unexpected new diploid Hieracium from Europe: Integrative taxonomic approach with a phylogeny of diploid Hieracium taxa. – Taxon 68: https://doi.org/10.1002/tax.12149

Abstract
Hieracium s.str. (Asteraceae) is one of the largest angiosperm genera notorious for its taxonomic complexity caused by widespread interspecific hybridization. This process is tightly coupled with polyploidization and apomixis – asexual reproduction by seeds, which has ensured the persistence of otherwise sterile interspecific hybrids. As a result, apomictic polyploid taxa dominate the taxonomic diversity of the genus whilst sexual diploid species are extremely rare and mostly confined to southern Europe. As diploid taxa are assumed to be the parents of apomictic lineages, the discovery of any new diploid species is important for understanding evolutionary processes and diversity patterns in the genus. Here, we describe a new diploid species, Hieracium vranceae, a narrow endemic to the Munţii Vrancei (Vrancea Mountains, Eastern Carpathians, Romania). This taxon with a distinctive morphology and a strong affinity to relic rocky habitats was first collected in 2013. This means that, even in Europe, some regions, like the Eastern Carpathians, are botanically underexplored and might still preserve an undiscovered diversity of plants. Phylogenetic analyses with multiple molecular markers (low‐copy nuclear genes gsh1 and sqs, nuclear ribosomal ETS, four cpDNA loci) applied to all diploid Hieracium species support specific rank for H. vranceae. In contrast, molecular data suggest conspecifity of two pairs of species, H. lucidum/H. cophanense from Sicily and H. naegelianum/H. renatae from the Balkans, which are moreover only weakly differentiated morphologically. Molecular (cpDNA) and cytogenetic (GISH, FISH) analyses furthermore revealed that H. vranceae has been involved as a maternal parent in the origin of an allotriploid apomictic species, H. telekianum, to which H. vranceae contributed one haplome. The other putative parents of H. telekianum are the diploid narrow endemic H. pojoritense and probably H. sparsum s.l. Our data thus stress the importance of interspecific hybridization for an evolutionary shift from sexuality to apomixis in Hieracium. Our findings furthermore highlight the significance of that part of the Carpathians as one of the most important evolutionary/refugial centres of Hieracium and suggest dynamic species ranges at a regional scale allowing physical contact of taxa whose distributional ranges are nowadays completely allopatric.”

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7 January 2020

Mráz P. & Zdvořák P. 2019: Reproductive pathways in Hieracium s.s. (Asteraceae): strict sexuality in diploids and apomixis in polyploids. – Ann. Bot. 123: 391–403.

Abstract
“Background and Aims: Apomixis or asexual seed reproduction is a key evolutionary mechanism in certain angiosperms providing them with reproductive assurance and isolation. Nevertheless, the frequency of apomixis is largely unknown, especially in groups with autonomous apomixis such as the diploid–polyploid genus Hieracium.
Methods:Using flow cytometric analyses, we determined the ploidy level and reproductive pathways (sexual vs. apomictic) for 7616 seeds originating from 946 plants belonging to >50 taxa sampled at 130 sites across Europe.
Key Results: Diploid seeds produced by diploids were formed exclusively by the sexual pathway after double fertilization of reduced embryo sacs. An absolute majority of tri- and tetraploid seeds (99.6 %) produced by tri- and tetrapolyploid taxa were formed by autonomous apomixis. Only 20 polyploid seeds (0.4 %) were formed sexually. These seeds, which originated on seven polyploid accessions of four taxa, were formed after fertilization of either unreduced embryo sacs through a so-called triploid bridge or reduced embryo sacs, and frequently resulted in progeny with an increased ploidy. In addition, the formation of seedlings with increased ploidy (4x and 6x) was found in two triploid plants. This is the first firm evidence on functional facultative apomixis in polyploid members of Hieracium sensu stricto (s.s.).
Conclusions: The mode of reproduction in Hieracium s.s. is tightly associated with ploidy. While diploids produce seeds exclusively sexually, polyploids produce seeds by obligate or almost obligate apomixis. Strict apomixis can increase the reproductive assurance and this in turn can increase the colonization ability of apomicts. Nevertheless, our data clearly show that certain polyploid plants are still able to reproduce sexually and contribute to the formation of new cytotypes and genotypes. The finding of functional facultative apomicts is essential for future studies focused on evolution, inheritance and ecological significance of apomixis in this genus.”