Logistic regression is a statistical tool widely used for predicting species' potential distributions starting from presence/absence data and a set of independent variables. However, logistic regression equations compute probability values based not only on the values of the predictor variables but also on the relative proportion of presences and absences in the dataset, which does not adequately describe the environmental favourability for or against species presence. A few strategies have been used to circumvent this, but they usually imply an alteration of the original data or the discarding of potentially valuable information. We propose a way to obtain from logistic regression an environmental favourability function whose results are not affected by an uneven proportion of presences and absences. We tested the method on the distribution of virtual species in an imaginary territory. The favourability models yielded similar values regardless of the variation in the presence/absence ratio. We also illustrate with the example of the Pyrenean desman's (Galemys pyrenaicus) distribution in Spain. The favourability model yielded more realistic potential distribution maps than the logistic regression model. Favourability values can be regarded as the degree of membership of the fuzzy set of sites whose environmental conditions are favourable to the species, which enables applying the rules of fuzzy logic to distribution modelling. They also allow for direct comparisons between models for species with different presence/absence ratios in the study area. This makes them more useful to estimate the conservation value of areas, to design ecological corridors, or to select appropriate areas for species reintroductions.

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The flat wasp family Bethylidae Haliday lacks global scale literature on their alpha taxonomy. The only world revision for the family was by Kieffer in 1914 and is fully out of date and somewhat useless; the only catalog for the family was made by Gordh & Móczár in 1990 and does not include hundreds of changes made since then; and the most recent world genera keys were proposed by Terayama in 2003, but do not reflect the current knowledge we have for the family. Given this scenario, we present a global guide of Bethylidae with diagnoses, taxonomic evaluation, keys, and a checklist of all their extant genera and subfamilies. We visited the main collections around the world, analyzed about 2,000 holotypes, and examined at least 400,000 specimens. To eliminate homonymies, we add the prefix “neo” to the original specific epithet when possible. The family is now composed by 2,920 species allocated in 96 genera distributed in eight subfamilies: Bethylinae, Pristocerinae, Epyrinae, Mesitiinae, Scleroderminae, Lancepyrinae, Holopsenellinae and Protopristocerinae. The latter three are extinct. One new family-group synonym is proposed: Fushunochrysidae Hong syn. nov. of Bethylidae. Two incertae sedis genera are allocated into Bethylinae: Cretobethylellus Rasnytsyn and Omaloderus Walker. One new genus-group synonym is revalidated: Pristepyris Kieffer stat. rev. from Acrepyris Kieffer. Sixteen new genus-group synonyms are proposed: Fushunochrysites Hong syn. nov. and Sinibethylus Hong syn. nov. of Eupsenella Westwood; Messoria Meunier syn. nov. of Goniozus Förster; Acrepyris Kieffer syn. nov. of Pristepyris Kieffer; Apristocera Kieffer syn. nov. and Parapristocera Brues syn. nov. of Pristocera Klug; Usakosia Kieffer syn. nov. of Prosapenesia Kieffer; Isobrachium Förster syn. nov., Leptepyris Kieffer syn. nov., Neodisepyris Kurian syn. nov., Rhabdepyris Kieffer syn. nov. of Epyris Westwood; Codorcas Nagy syn. nov., Hamusmus Argaman syn. nov. and Ukayakos Argaman syn. nov. of Heterocoelia Dahlbom; Domonkos Argaman syn. nov. of Incertosulcus Móczár; Ateleopterus Förster syn. nov. of Sclerodermus Latreille. One new genus-group synonym is revalidated: Topcobius Nagy syn. rev. of Sulcomesitius Móczár. One new genus-group revalidation is proposed: Incertosulcus Móczár stat. rev. from Anaylax Móczár. The following species-group nomenclatural acts are established: 153 new or revalidated combinations, 16 new names to avoid secondary homonyms, 11 species with revalidated status, and one synonym. Keys to the subfamilies and genera are provided. The text is supported by 599 illustrations organized onto 92 plates.

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Bonelli's eagle, Hieraaetus fasciatus , has recently suffered a severe population decline and is currently endangered. Spain supports about 70% of the European population. We used stepwise logistic regression on a set of environmental, spatial and human variables to model Bonelli's eagle distribution in the 5167 UTM 10 × 10 km quadrats of peninsular Spain. We obtained a model based on 16 variables, which allowed us to identify favourable and unfavourable areas for this species in Spain, as well as intermediate favourability areas. We assessed the stepwise progression of the model by comparing the model's predictions in each step with those of the final model, and selected a parsimonious explanatory model based on three variables -slope, July temperature and precipitation -comprising 76% of the predictive capacity of the final model. The reported presences in favourable and unfavourable areas suggest a source-sink dynamics in Bonelli's eagle populations. The fragmented spatial structure of the favourable areas suggests the existence of a superimposed metapopulation dynamics. Previous LIFE (The Financial Instrument of the European Union for the Environment and Nature) projects for the conservation of this species have focused mainly on the northern limit of its range, where the sharpest population decline has been recorded. In these areas, favourability is low and Bonelli's eagle populations are probably maintained by the immigration of juveniles produced in more favourable zones. However, southern populations, although stable, show signs of reduction in productivity, which could menace the population sizes in the whole study area. We suggest that conservation efforts should focus also on known favourable areas, which might favour population persistence in unfavourable areas through dispersal.