1,720,982 research outputs found
Between the hammer and the anvil: How the combined effect of global warming and the non-native common slider could threaten the european pond turtle
No full textThe European pond turtle Emys orbicularis is seriously threatened across Europe by the non-native common slider, Trachemys scripta, which is included among the 100 most invasive species worldwide. Using ensemble forecast techniques, we analysed the influence of climatic factors on the current distribution of these two species, subsequently projecting the obtained models under two Representative Concentration Pathways (RCPs) to 2050 and 2070, to investigate if global warming would boost direct competition within our study region. We implemented a gap analysis in GIS environment to assess how protected areas (PAs) may be affected by a loss of suitable area for E. orbicularis and by an expansion of T. scripta. An analysis of attitudinal range shift was evaluated, based on obtained projections. We found that both species may gain suitable area in the future, possibly because of the positive effect of increasing temperatures, and are predicted to shift from plain-to-hilly areas towards higher altitudes. These trends result in an increasing overlap of potentially suitable areas for both species, particularly within PAs; moreover, a niche analysis highlights that the results obtained are linked to the environmental niches of the two species. Our findings suggest the necessity, particularly for PAs' authorities, of field monitoring of T. scripta and further research to more comprehensively assess biotic and abiotic factors influencing the invasiveness of this species
Unravelling the taxonomic assessment of an interesting new species from Socotra island: Blepharidina socotrana sp. nov. (Coleoptera: Chrysomelidae)
Get PDFThe description of Blepharidina socotrana sp. nov. (Coleoptera: Chrysomelidae: Galerucinae: Alticini), with clear Afrotropical affi nities, from Socotra Island is provided. Photos of the main diagnostic morphological characters, including aedeagus, are supplied. A phylogenetic analysis of all species of Blepharidina Bechyné, 1968, performed to clarify the taxonomic position of the new species, confi rms the presence of two clades referable to as Blepharidina s. str. and B. (Afroblepharida Biondi & D’Alessandro, 2017), and places the new species within Afroblepharida, even though with a moderate support
Revealing the role of past and current climate in shaping the distribution of two parapatric European bats, Myotis daubentonii and M. capaccinii
Get PDFMarking tadpoles with Visible Implant Elastomer (VIE) tags: methods for improving readability and decreasing mortality.
Get PDFDESCRIPTIVE PROPERTIES OF I2-EMBEDDINGS
No full textWe contribute to the study of generalizations of the Perfect Set Property and the Baire Property to subsets of spaces of higher cardinalities, like the power set P(λ) of a singular cardinal λ of countable cofinality or products ∏i<ωλi for a strictly increasing sequence ⟨λi | i<ω⟩ of cardinals. We consider the question under which large cardinal hypotheses classes of definable subsets of these spaces possess such regularity properties, focusing on rank-into-rank axioms and classes of sets definable by Σ1-formulas with parameters from various collections of sets. We prove that ω-many measurable cardinals, while sufficient to prove the Perfect Set Property of all Σ1-definable sets with parameters in Vλ∪{Vλ}, are not enough to prove it if there is a cofinal sequence in λ in the parameters. For this conclusion, the existence of an I2-embedding is enough, but there are parameters in Vλ+1 for which I2 is still not enough. The situation is similar for the Baire Property: under I2 all sets that are Σ1-definable using elements of Vλ and a cofinal sequence as parameters have the Baire property, but I2 is not enough for some parameter in Vλ+1. Finally, the existence of an I0-embedding implies that all sets that are Σ1n-definable with parameters in Vλ+1 have the Baire property
Revision of the Afrotropical flea beetle subgenus Blepharidina s. str. Bechyné (Coleoptera, Chrysomelidae)
No full textA taxonomic revision of the species attributed to the flea beetle subgenus Blepharidina s. str. Bechyné, 1968 from sub- Saharan Africa is provided. The subgenus comprises 20 species, including the following six new species here described: B. aliquantula sp. nov. from Somalia, B. himba sp. nov. from Namibia, B. kasigauensis sp. nov., B. kenyana sp. nov., B. regalini sp. nov. from Kenya, and B. matabelelandensis sp. nov. from Zimbabwe. A key to all the species is given, with photos of their habitus, aedeagus, spermatheca, and main external diagnostic characters. Taxonomic notes, with considerations on similarities and affinities, and ecological data on the habitat preference for each species, are also reported
A European perspective of the conservation status of the threatened meadow viper Vipera ursinii (Bonaparte, 1835) (Reptilia, Viperidae)
Get PDFTaxonomic revision of the Calotheca parvula species group from southern Africa, with descriptions of three new species (Coleoptera, Chrysomelidae)
Get PDFCONVEX EMBEDDABILITY AND KNOT THEORY
No full textWe consider countable linear orders and study the quasi-order of convex embeddability and its induced equivalence relation. We obtain both combinatorial and descriptive set-theoretic results, and further extend our research to the case of circular orders. These results are then applied to the study of arcs and knots, establishing combinatorial properties and lower bounds (in terms of Borel reducibility) for the complexity of some natural relations between these geometrical objects
Addressing conservation measures through fine-tuned species distribution models for an Italian endangered endemic anuran
Get PDFClimate and land cover changes are the two most important stressors causing the decline of amphibians' populations worldwide. Within the Mediterranean area, one of the global biodiversity hotspots, the endemic Italian yellow-bellied toad (Bombina pachypus) suffered the same fate, as the decreases and local extinctions proved over time. Since the need to preserve this Apennine endemic species is evident, we take advantage of a novel approach combining climate-based ecological niche models and post-modelling GIS techniques (i.e., the weighted overlay framework) to produce finer species distribution models for B. pachypus. In doing so, we coupled climate variables with topographic-, hydrologic-, and habitat-related predictors, sharpening the potential species' distribution at its whole range scale. Our findings show a latitudinal subdivision in predicted suitability: Central Apennines populations are expected to suffer more than the Northern ones, with considerable potential future losses of genetic diversity. On the contrary, Southern Apennines' suitability is predicted to remain stable over time, preserving the vast di-versity. When assessing the coverage that protected areas offer to the locations of suitable habitats for B. pachypus, the protected sites of the Central Apennines result in slightly less suitable con-servation areas than those in the Northern and Southern Apennines. The overall protected areas coverage is currently low (similar to 20%) and predicted in the future to narrow towards medium suit-ability values, except in Southern Apennines, where an increase is inferred. In light of our spatially-explicit results, we suggest that a national-scale conservation strategy should consider different management options according to the sub-territories that our analyses highlighted. Our coupled "weighted modelling - spatialised genetic inference" approach permits us to support different conservation policies at all spatial scales, capitalising on relatively few input data. Also, in-depth spatial analyses should be performed to support effective protection strategies and management for the conservation stakeholders
- …
