Diatoms are present in all types of water bodies and their species diversity is influenced greatly by environmental conditions. This means that diatom occurrence and abundances are suitable indicators of water quality. Furthermore, continuous screening of algal biodiversity can provide information about diversity changes in ecosystems. Thus, diatoms represent a desirable group for which to develop an easy to use, quick, efficient, and standardised organism identification tool to serve routine water quality assessments. Because conventional morphological identification of diatoms demands specialised indepth knowledge, we have established standard laboratory procedures for DNA barcoding in diatoms. We (1) identified a short segment (about 400 bp) of the SSU (18S) rRNA gene which is applicable for the identification of diatom taxa, and (2) elaborated a routine protocol including standard primers for this group of microalgae. To test the universality of the primer binding sites and the discriminatory power of the proposed barcode region, 123 taxa, representing limnic diatom diversity, were included in the study and identified at species level. The effectiveness of the barcode was also scrutinised within a closely related species group, namely the Sellaphora pupula taxon complex and relatives.

Diatoms are frequently used for water quality assessments; however, identification to species level is difficult, time-consuming and needs in-depth knowledge of the organisms under investigation, as nonhomoplastic species-specific morphological characters are scarce. We here investigate how identification methods based on DNA (metabarcoding using NGS platforms) perform in comparison to morphological diatom identification and propose a workflow to optimize diatom fresh water quality assessments. Diatom diversity at seven different sites along the course of the river system Odra and Lusatian Neisse from the source to the mouth is analysed with DNA and morphological methods, which are compared. The NGS technology almost always leads to a higher number of identified taxa (270 via NGS vs. 103 by light microscopy LM), whose presence could subsequently be verified by LM. The sequence-based approach allows for a much more graduated insight into the taxonomic diversity of the environmental samples. Taxa retrieval varies considerably throughout the river system, depending on species occurrences and the taxonomic depth of the reference databases. Mostly rare taxa from oligotrophic parts of the river systems are less well represented in the reference database used. A workflow for DNA-based NGS diatom identification is presented. 28 000 diatom sequences were evaluated. Our findings provide evidence that metabarcoding of diatoms via NGS sequencing of the V4 region (18S) has a great potential for water quality assessments and could complement and maybe even improve the identification via light microscopy.

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This paper presents the findings of the Belmont Forum’s survey on Open Data which targeted the global environmental research and data infrastructure community. It highlights users’ perceptions of the term “open data”, expectations of infrastructure functionalities, and barriers and enablers for the sharing of data. A wide range of good practice examples was pointed out by the respondents which demonstrates a substantial uptake of data sharing through e-infrastructures and a further need for enhancement and consolidation. Among all policy responses, funder policies seem to be the most important motivator. This supports the conclusion that stronger mandates will strengthen the case for data sharing.

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The Lactucinae or Lactuca alliance include approximately 200 species distributed across the Northern Hemisphere and Africa. They were not recognised as a separate lineage until the late 20th century and their circumscription is still not fully settled. The generic classification of no other group of the Cichorieae has faced as many controversies as the Lactuca alliance and competing taxonomies coexist. This paper provides the first molecular phylogeny of the subtribe on a global scale as a major step towards its revised systematics. The sampling includes almost 60% of the species-level diversity and spans all species groups. Two datasets were created, one including the nrDNA ITS region, the other five concatenated non-coding plastid DNA loci. Maximum parsimony, maximum likelihood and Bayesian inference were used to produce a robust phylogenetic backbone. The diversification and expansion of the Lactucinae in a geohistorical context was reconstructed by estimating the age of their lineages using relaxed molecular clock dating and by inferring the ancestral areas using Bayesian binary analysis. The redelimited monophyletic Lactucinae are composed of seven lineages that also include Prenanthes, which is confirmed to have a single species, P. purpurea. The positions of two further lineages shift between Lactucinae and Crepidinae in the nuclear and plastid DNA phylogenies. Incongruence between the phylogenies suggests events of ancient reticulation or incomplete lineage sorting in the formation of these latter two lineages and in two of the seven other Lactucinae lineages. The phylogenetic results show a dilemma for Lactucinae systematics: most generic concepts proposed to date are highly artificial but the resolved phylogenetic lineages do not constitute practicable taxonomic entities with our current knowledge. Diversification of the subtribe is inferred to have taken place since the Middle Miocene. Biogeographic analysis proposes that the clade originated in the mountains of the landmass mediating between the European and Asian continents and delimited in the south by the Tethys Sea and in the north by the Paratethys Sea. Several independent migrations have occurred into various parts of Asia, Europe, tropical Africa and North America.

The explicit aim of the DNA Bank Network is to close the divide between biological specimen collections and molecular sequence databases. It provides a technically optimized DNA and tissue collection service facility in the interest of all biological research, with access to well-documented DNA-containing samples and voucher specimens as well as to corresponding molecular data stored in public sequence databases. The Network enables scientists to (i) query and order DNA samples of organisms collected from natural habitats via a shared Web portal, (ii) store DNA samples for reference under optimal conditions after project completion or data publication, (iii) obtain DNA material to conduct new studies or to extend and complement previous investigations, and (iv) support good scientific practice as the deposition of DNA samples and related specimens facilitates the verification of published results.

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