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The holotype of Galerina saxicola Svrček, a never revised species described from the Czech Republic in 1994, was studied in detail. Due to its poor state and the impossibility to obtain DNA data, we fixed its taxonomic position by designating an epitype using recent material from the type locality. The species proved to be conspecific with Norwegian and Czech collections of Galerina stordalii A.H.Sm., both morphologically and molecularly. Full synonymy and diagnostic characters of G. stordalii are provided, its morphological and ecological variability is discussed, and information on type specimens is corrected. Our collections document that G. stordalii has a broader ecological amplitude than thought before, living not only on Sphagnum and peat in boreal and arctic-alpine habitats like bogs and snow beds, but also among mosses in boggy spruce forests, on decaying conifer trunks in old-growth forests and on moist sandstone rocks in a river canyon under the influence of climatic inversion. [ABSTRACT FROM AUTHOR]

The genus Dyckia (Bromeliaceae) comprises more than 150 terrestrial or epilithic species with a strongly xeromorphic habit. Most of its members belong to the azonal rock vegetation of Neotropical savannas and forests of Brazil and adjacent countries. Dyckia is relatively species-rich compared with its closest relatives Encholirium (27 species) and Deuterocohnia (17 species). Here, we present the first molecular phylogenetic analysis of Dyckia using DNA sequence data from six plastid loci ( matK gene, rps16 intron, petD intron, rpl32- trnL, rps16- trnK and trnD- trnT) and a portion of the nuclear gene phyC. A total of 124 accessions were included, corresponding to 79 taxa from six genera. Phylogenetic trees were generated using parsimony, likelihood and Bayesian methods. DNA sequence variation among Dyckia species turned out to be extremely low, and phylogenies were poorly resolved. The monophyly of Dyckia is supported, whereas evidence is provided that Encholirium is paraphyletic. Based on a dated plastid DNA tree, Dyckia experienced a recent radiation starting around 2.9 million years ago. Four major clades could be identified that roughly correspond to the geographic origin of the samples. A parsimony network based on plastid DNA haplotypes shows a star-like pattern, indicating recent range expansions. Our data are compatible with a scenario where Dyckia and Encholirium diverged in northeastern Brazil, whereas one lineage of Dyckia dispersed to southern Brazil from where a rapid colonization of suitable habitats was initiated. We discuss our results in relation to species delimitation in Dyckia. [ABSTRACT FROM AUTHOR]

Crocussativus L. is a sterile species (3 n) whose origin has not been yet clarified. A lot of morphological studies supported the theory that it would have been originated from the evolution, or the hybridization, of other Crocus exemplars, especially C. thomasii, C. hadriaticus and C. cartwrightianus. Crocus sativus stigmas are saffron raw source but, because of their high economic value, sometimes this spice is adulterated. By the application of the DNA barcode technique, we analyzed different Crocus species genomes and we partially clarified some aspects of the phylogeny of this genus: in particular, C. sativus possible genetic derivation was elucidated. Our results also showed that different C. sativus species might have evolved by independent events, probably due to several geographical pressures. We demonstrated that barcoding method, usually adopted for interspecific taxonomic identification, could be also applied to intraspecific and population studies. Finally, we proposed this molecular approach as scientific tool able to discriminate and certificate saffron authenticity. [ABSTRACT FROM AUTHOR]

Recent studies have proposed a monophyletic circumscription of Filago and a new subgeneric treatment for this genus. The aim of this study was to analyse the nuclear genome size in a phylogenetic framework in order to evaluate the systematic significance of this trait to provide insights into the dynamics of genome size evolution and to assess relationships among DNA content, specific life and ecological features within the study group. A holoploid genome size of 76 samples corresponding to 27 taxa was determined using flow cytometry, which represents the first estimates of genome size in Bombycilaena, Filago, Ifloga and Logfia. Chromosome counts were performed for six species. Parsimony and Bayesian analysis of ITS, ETS and rpl32- trnL intergenic spacer sequence data were used to construct molecular phylogenetic trees. The evolution of genome size was investigated troughout the Brownian motion model with the three scaling parameters λ, κ and δ. The mean 2 C-value in the Filago group is relatively low (1.3644 ± 0.0079 pg) and homogeneous among species. A high degree of congruence was found between genome size distribution and the major phylogenetic lineages obtained. The generally accepted assumption that annual, ephemeral and autogamous species show low genome sizes was confirmed. Also the relatively high DNA contents found for a couple of species could be correlated with their highly specific ecological requirements. Phylogeny seems to represent the most important factor explaining the pattern of DNA amount variation in the Filago group. The DNA amount does not seem to be strongly influenced by selection. [ABSTRACT FROM AUTHOR]