Polyfázické přístupy v taxonomii zelených aerofytických řas

Conclusions Traditionaltaxonomyoftendependson single charactersusedfor distin- guishingparticularspecies.ln thisthesis,I haveillustratedapplicationofpoly- phasicapproachesin taxonomyof greenaerophyticalgae.Theseapproachesare basedon thecombinationof variouscharacters(traditionalmorphology,modern molphologicalapproaches,SSU, ITS rDNA andgeneintronsequencing)forthe speciesrecognitionin greenalgae. The morphologicalcharactersaloneareoftennot sufficientfor speciesde- lirnitation,thoughtheycan be usedfor routinespeciesidentificationModern rnorphologicalapproacheslike confocalmicroscopyallow to detectclearmor- phologicaldifferencesarnonginvestigatedcloselyrelatedspecies,evenifat first sightthesemorphologicallyvery uniformalgaehardlydifferatthe morphologi- cal level. A numberof rnorphologicalcharactersdoesnot reflectgeneticrela- tionships.Rathertheyareinfluencedby variousenvironmentalor culturecondi- tions.For example,cell dimensionsin Klebsorntidiuntcanbe distinctivelyinflu- encedby pH, humidity,illLrminationandternperatureconditions.However,with theaid of molecularmarkerswe candetectproperrnorphologicalfeaturesuseful for speciesdifferentiationt. ln .lslerochlorls,correlationtestof geneticdistances and morphologicaldifferencesrevealedusefulnessof particularchloroplast charactersforspeciesdelirnitation....Conclusions Traditionaltaxonomyoftendependson single charactersusedfor distin- guishingparticularspecies.ln thisthesis,I haveillustratedapplicationofpoly- phasicapproachesin taxonomyof greenaerophyticalgae.Theseapproachesare basedon thecombinationof variouscharacters(traditionalmorphology,modern molphologicalapproaches,SSU, ITS rDNA andgeneintronsequencing)forthe speciesrecognitionin greenalgae. The morphologicalcharactersaloneareoftennot sufficientfor speciesde- lirnitation,thoughtheycan be usedfor routinespeciesidentificationModern rnorphologicalapproacheslike confocalmicroscopyallow to detectclearmor- phologicaldifferencesarnonginvestigatedcloselyrelatedspecies,evenifat first sightthesemorphologicallyvery uniformalgaehardlydifferatthe morphologi- cal level. A numberof rnorphologicalcharactersdoesnot reflectgeneticrela- tionships.Rathertheyareinfluencedby variousenvironmentalor culturecondi- tions.For example,cell dimensionsin Klebsorntidiuntcanbe distinctivelyinflu- encedby pH, humidity,illLrminationandternperatureconditions.However,with theaid of molecularmarkerswe candetectproperrnorphologicalfeaturesuseful for speciesdifferentiationt. ln .lslerochlorls,correlationtestof geneticdistances and morphologicaldifferencesrevealedusefulnessof particularchloroplast charactersforspeciesdelirnitation....Department of BotanyKatedra botanikyFaculty of SciencePřírodovědecká fakult

Polyphasic approaches in the taxonomy of green aerophytic algae

Conclusions Traditionaltaxonomyoftendependson single charactersusedfor distin- guishingparticularspecies.ln thisthesis,I haveillustratedapplicationofpoly- phasicapproachesin taxonomyof greenaerophyticalgae.Theseapproachesare basedon thecombinationof variouscharacters(traditionalmorphology,modern molphologicalapproaches,SSU, ITS rDNA andgeneintronsequencing)forthe speciesrecognitionin greenalgae. The morphologicalcharactersaloneareoftennot sufficientfor speciesde- lirnitation,thoughtheycan be usedfor routinespeciesidentificationModern rnorphologicalapproacheslike confocalmicroscopyallow to detectclearmor- phologicaldifferencesarnonginvestigatedcloselyrelatedspecies,evenifat first sightthesemorphologicallyvery uniformalgaehardlydifferatthe morphologi- cal level. A numberof rnorphologicalcharactersdoesnot reflectgeneticrela- tionships.Rathertheyareinfluencedby variousenvironmentalor culturecondi- tions.For example,cell dimensionsin Klebsorntidiuntcanbe distinctivelyinflu- encedby pH, humidity,illLrminationandternperatureconditions.However,with theaid of molecularmarkerswe candetectproperrnorphologicalfeaturesuseful for speciesdifferentiationt. ln .lslerochlorls,correlationtestof geneticdistances and morphologicaldifferencesrevealedusefulnessof particularchloroplast charactersforspeciesdelirnitation...

Chrysosphaerella rotundata Skaloudova & Skaloud 2013, sp. nov.

Chrysosphaerella rotundata Škaloudová & Škaloud, sp. nov. (Figs. 1–6) Colonies spherical, consisting of cells bearing two flagella. Cells covered by numerous scales and spines. Three size classes of scales occur: large circular scales (3.0–3.5 × 2.2–3.1 µm), large oval scales (2.0–3.1 × 1.3–2.4 µm), and smaller oval scales (1.5–1.7 × 1.2 µm). Scales patterned with a series of short ridges forming a scalloped shaped pattern. Spines with a shaft joining the two plates of the bobbin-like structure. The length of the spines varies from 4 µm to 10 µm. Cysts unknown. Type:— FINLAND. Keski-Suomi, 62° 15' 1.07" N, 26° 34' 48.00" E, a small, oligotrophic unnamed lake, water temperature 5.6 °C, pH 7, conductivity 40 µS cm -1, coll. Škaloudová & Škaloud, 1 May 2012 (holotype: Strain S 89.C4, frozen material deposited at the Culture Collection of Algae of the Charles University in Prague, Department of Botany, Benátská 2, 12801 Prague 2, Czech Republic). Fig. 2 is an illustration of the holotype. Cells were grouped into spherical colonies. Individual cells were spherical to pyriform, about 12–13 Μm long and 11 Μm wide, bearing two flagella. Cells were covered by numerous scales and spines. Three size classes of scales might be discerned; however, a continuous transition in size of scales existed. The majority of the scales were larger and oval in outline (Figs. 1, 3). The second type of the scales, larger and circular in outline, were produced less frequently (Fig. 2). However, presence of the large, circular-shaped scales was a main distinguishing character of Chrysosphaerella rotundata. Both large circular and oval scales were patterned with a series of short ridges forming a scalloped shaped pattern. The pattern of smaller oval scales (Fig. 3) was the same as that of larger scales, but often less distinct. The spines had a thick shaft joining the two plates of the bobbin-like structure (Figs. 4–5); however, a variation in the thickness of the shaft was observed and spines with a thinner shaft were found as well (Fig. 6). Etymology:— The specific epithet 'rotundata' refers to the rounded shape of scales. Phylogenetic analyses, ITS2 secondary structures:— Bayesian inference, Maximum Likelihood, and Maximum Parsimony analyses inferred from the concatenated SSU rDNA and rbc L sequences resulted in highly similar phylogenetic trees, recognizing the six main lineages within Chrysophyceae (Fig. 7). According to their members, the lineages could be recognized as traditionally defined orders: Chromulinales, Chrysosaccales, Hibberdiales, Hydrurales, Ochromonadales, and Synurales. With the exception of the Ochromonadales, all lineages were also significantly supported by ML and wMP analyses. Both analyses resolved the Ochromonadales as monophyletic, but without any statistical support. The genus Chrysosphaerella formed a firmly supported monophyletic lineage within the Chromulinales (Fig. 7). It was divided into two supported subclades. Chrysosphaerella rotundata was inferred as closely related to morphologically similar C. brevispina, with which it formed the first inferred subclade. The species differed by eight and eleven nucleotide substitution changes in the SSU rDNA and rbc L sequences, respectively. The second subclade consisted of C. longispina and two environmental Chrysosphaerella isolates. Since the isolates were molecularly characterized by only the SSU rDNA (summer isolate) or rbc L (winter isolate) sequence, we could not exclude that they in fact belong to the same genotype. The environmental isolates differed by two nucleotide substitution changes in the SSU rDNA and rbc L sequences from the C. longispina sequences. To further evaluate the degree of genetic differentiation of the closely related C. rotundata and C. brevispina, we additionally sequenced the ITS1- 5.8S rDNA-ITS2 region. The ITS1 region was hardly alignable, and the sequences differed significantly in their length (342 bp in C. rotundata vs. 294 bp in C. brevispina). Within the aligned regions, the divergence between the ITS1 rDNA sequences was approximately 15.5%. The length of the ITS2 region was similar in both species (293 bp in C. rotundata vs. 287 bp in C. brevispina), and the overall divergence between the ITS2 rDNA sequences was approximately 12.5%. In addition, we mapped the differences in the ITS2 sequence on a predicted ITS2 secondary structure (Fig. 8). Most of the differences were located in terminal and internal hairpin loops. Four compensatory base changes (CBCs) were found in the stem regions of helices I and II.Published as part of Škaloudová, Magda & Škaloud, Pavel, 2013, A new species of Chrysosphaerella (Chrysophyceae: Chromulinales), Chrysosphaerella rotundata sp. nov., from Finland, pp. 34-42 in Phytotaxa 130 (1) on page 37, DOI: 10.11646/phytotaxa.130.1.4, http://zenodo.org/record/508577

<i>Rindifilum ramosum</i> gen. nov., sp. nov., un nouveau genre d’eau douce au sein des Ulvales (Ulvophyceae, Chlorophyta)

Le présent article fournit une étude phylogénétique et morphologique de deux souches qui s’avèrent représenter un genre nouveau et une espèce nouvelle, Rindifilum ramosum gen. nov., sp. nov., au sein de la famille des Ctenocladiaceae (Ulvales). Rindifilum ramosum gen. nov., sp. nov. se développe en association avec le genre Verrucaria Schrader, un ascomycète lichénisé. Les reconstructions phylogénétiques basées sur les gènes rbcL, 18S rRNA et tufA ont montré que les souches étudiées appartiennent à une lignée distincte de celles séquencées jusqu’à présent. De plus, les comparaisons basées sur les observations morphologiques n’ont révélé aucune différence entre les deux souches. Le nouveau genre Rindifilum gen. nov. présente une combinaison unique de caractéristiques morphologiques, comme les cellules en forme de « poire » qui se développent directement en un « filament en forme de marteau », ce qui le distingue de toutes les autres algues vertes décrites jusqu’à présent.The present paper provides a phylogenetic and morphological study of two strains that turn out to represent a new genus and species, Rindifilum ramosum gen. nov., sp. nov., within the family Ctenocladiaceae (Ulvales). Rindifilum ramosum gen. nov., sp. nov. grows in association with the lichenized ascomycetes genus Verrucaria Schrader. Phylogenetic reconstructions based on the rbcL, 18S rRNA and tufA genes showed that the investigated strains belonged to a lineage distinct from those sequenced so far. Moreover, comparisons based on morphological observations revealed no differences between the two strains. The newly genus Rindifilum gen. nov. exhibits a unique combination of morphological features, as the “pear-shaped” cells that develop directly into a “hammer-shaped filament”, making it distinct from all other green algae described so far.</p

Diversity of subaerial algae and cyanobacteria growing on bark and wood in the lowland tropical forests of Singapore

Background and aims – Knowledge on diversity and distribution of algae and cyanobacteria in subaerial habitats still lags behind those of freshwater and marine environments. Notably, data on diversity of microalgae in tropical corticolous habitats are still scarce. We investigated species composition of subaerial epixylic algae and cyanobacteria from two Singaporean rainforest localities. We asked whether there are differences in species composition and alpha-diversity of samples taken in different areas and in different habitat types (bark vs. decaying bare wood). In addition, we asked whether there are differences in species turnover (beta-diversity) among different habitat types and areas. Methods – The cultivation-based approach and the microscopic analysis of populations were used. In total, 20 samples of bark and decaying wood from two forested areas were analyzed. Statistical analyses involved the non-metric multidimensional scaling (NMDS) of species data. Significance of differences in algal composition between groups of samples was evaluated by the non-parametric two-way ANOSIM (Analysis of Similarities) using the crossed design with permutations in blocks. The SIMPER method was used to identify species that characteristically discriminate between habitat types and sampling areas. Key results – In total, 57 species were identified. Green algae (Trebouxiophyceae, Chlorophyceae, Trentepohliales) were dominant, and Cyanobacteria were the second most frequent group. The dominants of the subaerial assemblages differed from corresponding temperate habitats and, in addition, their alpha-diversity was considerably higher. Several green algal morphospecies were characteristic for the bark localities (e.g. Dictyochloropsis spp., Pseudomarvania aerophytica, Printzina effusa and Printzina lagenifera). The alpha-diversity was similar in both habitat types, but the species turnover among samples (beta-diversity) was significantly higher in the decaying wood samples. Conclusions – Tropical corticolous habitats probably harbour higher diversity than corresponding temperate habitats. High beta-diversity of decaying wood illustrates general importance of this substrate for biodiversity of subaerial algae in the tropics

Splitting of Micrasterias fimbriata (Desmidiales, Viridiplantae) into two monophyletic species and description of Micrasterias compereana sp. nov.

Background – Micrasterias fimbriata, a conspicuous desmid species, has recently been shown to be composed of two clearly delimited monophyletic clades within the genus Micrasterias, closely related to several other well-defined Micrasterias species ( M. brachyptera, M. rotata, M. torreyi ). The members of both clades can also be unambiguously recognized by careful morphological analysis. In addition, their distribution areas in Europe and North America are largely vicariant. Interestingly, morphological features of one of the clades do not correspond with any of the previously described infraspecific taxa of M. fimbriata . Material and methods – The study was based on a combination of morphological and molecular phylogenetic analyses of the clonal strains and natural populations. Key results and conclusions – In this study, we present formal taxonomic description of Micrasterias compereana for specimens formerly included within traditional M. fimbriata, but differring in their phylogenetic position and discriminative morphological characteristics. Phylogenetic analysis was based on the nuclear 18S rDNA and the plastid-encoded trnG UCC intron sequence data. Morphological differences between species were illustrated by light and scanning electron microscopy. The analysis of natural samples, strains and published records showed that M. compereana occurs in North America and western Europe. Conversely, M. fimbriata sensu stricto probably only occurs in temperate and boreal regions of Europe and Asia

Everything is NOT everywhere: network and trait-based approaches to microbial communities

International audienc

Ecological and biogeographical drivers of freshwater green algae biodiversity: from local communities to large-scale species pools of desmids

International audienc