Neonicotinoid pesticides were first introduced in the mid-1990s, and since then, their use has grown rapidly. They are now the most widely used class of insecticides in the world, with the majority of applications coming from seed dressings. Neonicotinoids are water-soluble, and so can be taken up by a developing plant and can be found inside vascular tissues and foliage, providing protection against herbivorous insects. However, only approximately 5% of the neonicotinoid active ingredient is taken up by crop plants and most instead disperses into the wider environment. Since the mid-2000s, several studies raised concerns that neonicotinoids may be having a negative effect on non-target organisms, in particular on honeybees and bumblebees. In response to these studies, the European Food Safety Authority (EFSA) was commissioned to produce risk assessments for the use of clothianidin, imidacloprid and thiamethoxam and their impact on bees. These risk assessments concluded that the use of these compounds on certain flowering crops poses a high risk to bees. On the basis of these findings, the European Union adopted a partial ban on these substances in May 2013. The purpose of the present paper is to collate and summarise scientific evidence published since 2013 that investigates the impact of neonicotinoids on non-target organisms. Whilst much of the recent work has focused on the impact of neonicotinoids on bees, a growing body of evidence demonstrates that persistent, low levels of neonicotinoids can have negative impacts on a wide range of free-living organisms.

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Diaporthe (Phomopsis) species have often been reported as plant pathogens, non-pathogenic endophytes or saprobes, commonly isolated from a wide range of hosts. The primary aim of the present study was to resolve the taxonomy and phylogeny of a large collection of Diaporthe species occurring on diverse hosts, either as pathogens, saprobes, or as harmless endophytes. In the present study we investigated 243 isolates using multilocus DNA sequence data. Analyses of the rDNA internal transcribed spacer (ITS1, 5.8S, ITS2) region, and partial translation elongation factor 1-alpha (TEF1), beta-tubulin (TUB), histone H3 (HIS) and calmodulin (CAL) genes resolved 95 clades. Fifteen new species are described, namely Diaporthe arengae, D. brasiliensis, D. endophytica, D. hongkongensis, D. inconspicua, D. infecunda, D. mayteni, D. neoarctii, D. oxe, D. paranensis, D. pseudomangiferae, D. pseudophoenicicola, D. raonikayaporum, D. schini and D. terebinthifolii. A further 14 new combinations are introduced in Diaporthe, and D. anacardii is epitypified. Although species of Diaporthe have in the past chiefly been distinguished based on host association, results of this study confirm several taxa to have wide host ranges, suggesting that they move freely among hosts, frequently co-colonising diseased or dead tissue. In contrast, some plant pathogenic and endophytic taxa appear to be strictly host specific. Given this diverse ecological behaviour among members of Diaporthe, future species descriptions lacking molecular data (at least ITS and HIS or TUB) should be strongly discouraged.

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Background The nematode Caenorhabditis elegans is a major model organism in laboratory biology. Very little is known, however, about its ecology, including where it proliferates. In the past, C. elegans was mainly isolated from human-made compost heaps, where it was overwhelmingly found in the non-feeding dauer diapause stage. Results C. elegans and C. briggsae were found in large, proliferating populations in rotting plant material (fruits and stems) in several locations in mainland France. Both species were found to co-occur in samples isolated from a given plant species. Population counts spanned a range from one to more than 10,000 Caenorhabditis individuals on a single fruit or stem. Some populations with an intermediate census size (10 to 1,000) contained no dauer larvae at all, whereas larger populations always included some larvae in the pre-dauer or dauer stages. We report on associated micro-organisms, including pathogens. We systematically sampled a spatio-temporally structured set of rotting apples in an apple orchard in Orsay over four years. C. elegans and C. briggsae were abundantly found every year, but their temporal distributions did not coincide. C. briggsae was found alone in summer, whereas both species co-occurred in early fall and C. elegans was found alone in late fall. Competition experiments in the laboratory at different temperatures show that C. briggsae out-competes C. elegans at high temperatures, whereas C. elegans out-competes C. briggsae at lower temperatures. Conclusions C. elegans and C. briggsae proliferate in the same rotting vegetal substrates. In contrast to previous surveys of populations in compost heaps, we found fully proliferating populations with no dauer larvae. The temporal sharing of the habitat by the two species coincides with their temperature preference in the laboratory, with C. briggsae populations growing faster than C. elegans at higher temperatures, and vice at lower temperatures.

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A monographic revision of the hyphomycete genus Cladosporium s. lat. (Cladosporiaceae, Capnodiales) is presented. It includes a detailed historic overview of Cladosporium and allied genera, with notes on their phylogeny, systematics and ecology. True species of Cladosporium s. str. (anamorphs of Davidiella), are characterised by having coronate conidiogenous loci and conidial hila, i.e., with a convex central dome surrounded by a raised periclinal rim. Recognised species are treated and illustrated with line drawings and photomicrographs (light as well as scanning electron microscopy). Species known from culture are described in vivo as well as in vitro on standardised media and under controlled conditions. Details on host range/substrates and the geographic distribution are given based on published accounts, and a re-examination of numerous herbarium specimens. Various keys are provided to support the identification of Cladosporium species in vivo and in vitro. Morphological datasets are supplemented by DNA barcodes (nuclear ribosomal RNA gene operon, including the internal transcribed spacer regions ITS1 and ITS2, the 5.8S nrDNA, as well as partial actin and translation elongation factor 1-α gene sequences) diagnostic for individual species. In total 993 names assigned to Cladosporium s. lat., including Heterosporium (854 in Cladosporium and 139 in Heterosporium), are treated, of which 169 are recognized in Cladosporium s. str. The other taxa are doubtful, insufficiently known or have been excluded from Cladosporium in its current circumscription and re-allocated to other genera by the authors of this monograph or previous authors. Taxonomic novelties Cladosporium allicinum (Fr.: Fr.) Bensch, U. Braun & Crous, comb. nov., C. astroideum var. catalinense U. Braun, var. nov., Fusicladium tectonicola (Yong H. He & Z.Y. Zhang) U. Braun & Bensch, comb. nov., Septoidium uleanum (Henn.) U. Braun, comb. nov., Zasmidium adeniae (Hansf.) U. Braun, comb. nov., Zasmidium dianellae (Sawada & Katsuki) U. Braun, comb. nov., Zasmidium lythri (Westend.) U. Braun & H.D. Shin, comb. nov., Zasmidium wikstroemiae (Petch) U. Braun, comb. nov.

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Fungal taxonomists routinely encounter problems when dealing with asexual fungal species due to poly- and paraphyletic generic phylogenies, and unclear species boundaries. These problems are aptly illustrated in the genus Phoma. This phytopathologically significant fungal genus is currently subdivided into nine sections which are mainly based on a single or just a few morphological characters. However, this subdivision is ambiguous as several of the section-specific characters can occur within a single species. In addition, many teleomorph genera have been linked to Phoma, three of which are recognised here. In this study it is attempted to delineate generic boundaries, and to come to a generic circumscription which is more correct from an evolutionary point of view by means of multilocus sequence typing. Therefore, multiple analyses were conducted utilising sequences obtained from 28S nrDNA (Large Subunit - LSU), 18S nrDNA (Small Subunit - SSU), the Internal Transcribed Spacer regions 1 & 2 and 5.8S nrDNA (ITS), and part of the beta-tubulin (TUB) gene region. A total of 324 strains were included in the analyses of which most belonged to Phoma taxa, whilst 54 to related pleosporalean fungi. In total, 206 taxa were investigated, of which 159 are known to have affinities to Phoma. The phylogenetic analysis revealed that the current Boeremaean subdivision is incorrect from an evolutionary point of view, revealing the genus to be highly polyphyletic. Phoma species are retrieved in six distinct clades within the Pleosporales, and appear to reside in different families. The majority of the species, however, including the generic type, clustered in a recently established family, Didymellaceae. In the second part of this study, the phylogenetic variation of the species and varieties in this clade was further assessed. Next to the genus Didymella, which is considered to be the sole teleomorph of Phoma s. str., we also retrieved taxa belonging to the teleomorph genera Leptosphaerulina and Macroventuria in this clade. Based on the sequence data obtained, the Didymellaceae segregate into at least 18 distinct clusters, of which many can be associated with several specific taxonomic characters. Four of these clusters were defined well enough by means of phylogeny and morphology, so that the associated taxa could be transferred to separate genera. Aditionally, this study addresses the taxonomic description of eight species and two varieties that are novel to science, and the recombination of 61 additional taxa.

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