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A miniaturized QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Save) approach combined with gas chromatography-tandem mass spectrometry (GC-MS/MS) has been developed for the simultaneous determination of nine pesticides (Cyflufenamide, Difenoconazole, Dimethomorph, Fluopicolide, Fluopyram, Metrafenone, Myclobutanil, Quinoxyfen, and Tebuconazole) in insects, snails, and spiders. In contrast to the original QuEChERS approach, only 500 mg of dried and homogenized sample matrix, mixed with 1.0 mL ethyl acetate and 250 mg MgSO:NaCl (4:1), is required for this novel 'micro-QuEChERS' protocol. The organic phase was cleaned using dispersive solid-phase extraction (dSPE) with 75 mg MgSO:PSA sorbent (4:1). The method was validated according to SANCO/12571/2013 and applied to real samples ( n = 7). Fluopicolide was the only detectable pesticide in real samples from vineyards. In two samples, the Fluopicolide levels were between the determined LOD and LOQ (0.15-1.00 mg kg), and in one sample a concentration of 1.68 mg kg was detected. [ABSTRACT FROM AUTHOR]

Parapatry is a remarkable distributional pattern where the ranges of two species come into contact but only narrowly overlap. Theory predicts and empirical data suggest that parapatric range margins are most likely to form along environmental gradients when there is interspecific competition. Here, we study the ecology of the narrow contact zones of two parapatric European land salamanders, S alamandra salamandra and S alamandra atra. Previous research showed that abiotic conditions determine parapatric range margins of these two species. However, in contrast to other parapatric salamander species and theoretical predictions, there is no evidence for competitive interactions in the two S alamandra species. To study whether competition restricts these species' ranges and to understand local syntopic co-occurrence within their contact zones, we used site-occupancy models (1) to assess species-habitat relationships and (2) to test whether there is evidence for competition. We found that the two salamanders show dissimilar species-habitat relationships. The slope of the site positively affected the site-occupancy probability of S . salamandra, while none of the habitat characteristics explained the occupancy probability of S . atra. The local presence of one species had no effect on the occupancy probability of the other, suggesting that there is no effect of competition on local occurrence or that competition does not lead to spatial segregation. To fully understand the mechanisms that determine the parapatric range margins between the salamander species and to unravel the role of interspecific interactions, it is necessary to further study species' functional traits. [ABSTRACT FROM AUTHOR]

The Asian Harlequin ladybird ( Harmonia axyridis) is a globally invasive alien species. We developed species distribution models (SDMs) aiming at an explanation of the observed native and invasive distributions and the prediction of the species' potential distribution. SDMs were built based on bioclim parameters with Maxent (i) on known native occurrence only (SDMnat), (ii) on known European invasive occurrence only (SDMinv) and (iii) by combining both previous approaches (SDMall). Results indicate that SDMinv match the observed European invasive range better than SDMnat or SDMall. The origin of Asian founders in Europe remains unknown. SDMinv highlighted a restricted area in China which may represent the region of origin of the European Harlequin ladybird, leaving the possibility of within-species climate niche variation. As a result, when targeting the worldwide potential of invasiveness of H. axyridis, SDMall may reveal maximum results uncovering the species' potential distribution. These results have to be seen in the framework of conceptual problems and pitfalls when generating SDMs including niche definition, niche shift, sampling bias, biological importance of predictors and model transferability uncertainties. [ABSTRACT FROM AUTHOR]

Chydridiomycosis is an infectious emerging disease in amphibians that has been directly linked to mass mortality, drastic population decline and extinction. The understanding of the factors limiting the distribution and the abundance of its biological agent, the amphibian chytrid fungus Batrachochytrium dendrobatidis ( Bd ), is still limited. It has been suggested that climate plays a key role. A recent study conducted infection surveys at 31 lowland sites on the Australian East coast and searched for climatic variables explaining Bd prevalence and intensity in Stony creek frogs Litoria lesueuri (complex). A link between the prevalence of infections and latitude was advocated, exclusively focusing on the pathogen. Beyond this, the prevalence and intensity of Bd infection may also depend on the climatic suitability of a given site for the amphibian host. Herein, we extend the previous study using a set of long-term bioclimatic variables and assess climatic suitability for Stony creek frogs at the sites previously studied for Bd. We ran a Climatic Envelope Model for our target amphibian based on those variables with the most explanatory power for prevalence and intensity, thus representing the link between climatic suitability for both the pathogen and the host. Our findings allow the hypothesis that there exists a significant correlation between climatic suitability for Stony creek frogs at the previously studied sites and latitude. At the same time, this was congruent with the latitudinal gradient of the number of zoospores per frog. [ABSTRACT FROM AUTHOR]

Sympatric reed frog species were studied in Gabon (Monts Cristal: Hyperolius mosaicus , H. pardalis , H. tuberculatus ) and Kenya (Kakamega Forest: Hyperolius acuticeps , H . cf. cinnamomeoventris , H. kivuensis , H. lateralis , H. viridiflavus ). For each taxon, a standardized diagnosis covering 11 aspects of adult and in part tadpole morphology as well as the sequence of a 560 bp fragment of mitochondrial DNA of the 16S ribosomal gene are provided. In addition, behavioural data are given for each species including measurable parameters of advertisement calls. The Monts Cristal Hyperolius species clearly differ in their spatial arrangement through the choice of breeding site. Hyperolius species at the Kakamega Forest share the same breeding sites but in part differ in their activity pattern throughout the year. Advertisement calls of sympatric species in both regions mainly differ in temporal parameters. [ABSTRACT FROM AUTHOR]

The advertisement calls of the following Neotropical poison frog species (Dendrobatidae) are described: Colostethus brunneus, Dendrobates imitator yurim-aguensis, D. leucomelas and two populations referable to Epipedobates boulengeri. Oscillograms, audiospectrograms and measurements of vocalizations are provided. Advertisement calls of C. brunneus are similar to possible related species, while D. leucomelas vocalizations deviate from suggested phylogenetic relatives. Advertisement calls of D. imitator yurimaguensis do not differ from those of D. i. imitator; the validity of the former is doubted. Bioacoustics provide evidence that E. boulengeri could probably comprise a complex of at least two species. Five formerly suggested call types are re-defined using measurable characters. As far as possible, the 71 dendrobatid frog species for which advertisement calls have been described are allocated. [ABSTRACT FROM AUTHOR]

A phylogenetic analysis of the Neotropical dart-poison frogs, genus Phyllobates, was performed based on mitochondrial cytochrome b sequences. Members of Phyllobates from South and Central America were found to form each an evolutionary lineage. Among the South American lineage, species with uniform dorsal coloration as adults form a derived monophyletic clade. [ABSTRACT FROM AUTHOR]