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The aim of this study was to unravel the relative role played by speleogenesis (i.e., the process in which a cave is formed), landscape-scale variables, and geophysical factors in the determination of species richness in caves. Biological inventories from 21 caves located in the southeastern Iberian Peninsula along with partial least square (PLS) regression analysis were used to assess the relative importance of the different explanatory variables. The caves were grouped according to the similarity in their species composition; the effect that spatial distance could have on similarity was also studied using correlation between matrices. The energy and speleogenesis of caves accounted for 44.3% of the variation in species richness. The trophic level of each cave was the most significant factor in PLS regression analysis, and epigenic caves (i.e., those formed by the action of percolating water) had significantly more species than hypogenic ones (i.e., those formed by the action of upward flows in confined aquifers). Dissimilarity among the caves was very high (multiple-site β sim = 0.92). Two main groups of caves were revealed through the cluster analysis, one formed by the western caves and the other by the eastern ones. The significant-but low-correlation found between faunistic dissimilarity and geographical distance (r = .16) disappeared once the caves were split into the two groups. The extreme beta-diversity suggests a very low connection among the caves and/or a very low dispersal capacity of the species. In the region under study, two main factors are intimately related to the richness of terrestrial subterranean species in caves: the amount of organic material (trophic level) and the formation process (genesis). This is the first time that the history of a cave genesis has been quantitatively considered to assess its importance in explaining richness patterns in comparison with other factors more widely recognized.

Although Iberian subsurface terrestrial habitats have been sampled for a half century, they remain poorly known. During the last five years much more sampling of these subsurface habitats has been made, mainly in scree slopes (also called colluvial Mesovoid Shallow Substratum habitats, MSS) but also in alluvial debris of temporal watercourses (alluvial MSS). In our study, diplurans, a basal hexapod group, were extracted from two hundred traps installed in 69 locations in the mountain ranges of six different regions of the Iberian Peninsula, from north to south: Cantabrian, Pyrenees, Iberic System, Central System, Prebaetic and Penibaetic Mountains. A total of 1251 specimens in fifteen dipluran species: thirteen described Campodeidae, one described Japygidae and one new Campodea species inhabiting the alluvial MSS habitats of the watercourses of Prebaetic Mountains. A few populations of these dipluran species show troglobiomorphic features as a consequence of the medium-sized voids of the MSS habitats, such as Campodea grassii Silvestri, 1912, collected in a scree slope connected with a deep subterranean system in Penyas Roset, Prebaetic Mountains. Most species found in MSS habitats are endogean or epiedaphic species living in the area, but this is not the case in Sierra de Guadarrama, where three species (Campodea propinqua Silvestri, 1932, Campodea neusae Sendra & Moreno, 2006 and Campodea zuluetai Silvestri, 1932) unknown in the soil of these mountains have appeared in these subsurface terrestrial habitats.

An accurate estimation of the expected consequences of climate change requires the proper quantification of the effect of climate on current species distributions. Several interrelated sources of uncertainty may affect the likelihood of species distribution models (SDMs) to determine the relative importance of climate. Our aim was to assess the relationship between the influence of geographical background (GB) delimitation and that of subtracting the non-climate effects from the weight of climatic predictors to estimate the combined influence of these two factors on predictions in climate change scenarios. The distribution of 40 endemic mammals in Western Europe have been modeled by (i) using the whole territory of Western Europe as the GB and also specifically delimiting the GB with a geographical criterion and (ii) considering climatic predictors in addition to other non-climatic variables in order to extract the pure effect of climate. The models were used to quantify species’ sensitivity to new climate scenarios. Results showed discrepancies among the analytical approaches. Changes in distribution obtained by considering the pure effect of climate were lower than those obtained by considering the apparent effect, and GB-delimited models yielded higher changes than those trained in Western Europe. We evidence that climate weighting and GB delimitation have dramatic influences on the projections of models when transferred to new scenarios. We emphasize that scientific studies and derived adaptation policies based on SDMs without an explicit consideration of the GB and the weighting of the climate-related variables may be misleading and in need of revision.

While ecological effects on short-term population dynamics are well understood, their effects over millennia are difficult to demonstrate and convincing evidence is scant. Using coalescent methods, we analysed past population dynamics of three lizard species (Psammodromus hispanicus, P. edwardsianus, P. occidentalis) and linked the results with climate change data covering the same temporal horizon (120,000 years). An increase in population size over time was observed in two species, and in P. occidentalis no change was observed. Temporal changes in temperature seasonality and the maximum temperature of the warmest month were congruent with changes in population dynamics observed for the three species and both variables affected population density, either directly or indirectly (via a life-history trait). These results constitute the first solid link between ecological change and long-term population dynamics. The results moreover suggest that ecological change leaves genetic signatures that can be retrospectively traced, providing evidence that ecological change is a crucial driver of genetic diversity and speciation.

© 2015, Springer International Publishing Switzerland. In this study, the invertebrate fauna of a colluvial Mesovoid Shallow Substratum (MSS) is Eastern Spain was characterized, and the importance of the MSS as refuge for endemic and rare species was assessed. Ten pitfall traps were buried up to 1 m deep inside multiperforated PVC tubes across a stone debris. Several environmental variables were measured in each sampling point. The completeness of the inventory was assessed, and different diversity patterns—variation in abundance, species richness and species composition—were analyzed. 4150 individuals and 164 species were captured, most of them arthropods. The number of individuals and species varied considerably among traps. Half of the species were represented by one or two individuals, and neither the species accumulation curves nor the curves for the non-parametric estimators showed any sign of stabilizing. Individuals of abundant species aggregated in one or a few traps. No consistent diversity patterns were found, except that distance among traps partially explained the similarity in species composition when considering only the most abundant species. This is a very rich but uneven assemblage that shows a high degree of species turnover between traps. One-sixth of the species can be classified as either troglobionts or troglophiles, but there is a significant presence of edaphic species. Obtaining complete fauna inventories in the MSS has proven to be a challenging task. The study of the MSS reveals important faunistic information, providing new taxa to science as well as interesting records of poorly known species.

The evaluation of species distribution models (SDMs) is a crucial step; usually, a random subsample of data is used to test prediction capacity. This procedure, called cross-validation, has been recently shown to overestimate SDMs performance due to spatial autocorrelation. In the case of expanding species, there exists the possibility to test the predictions with non-random geographically structured data, i.e., a new data set which corresponds to the last occupied localities. The aim of this study was to evaluate the capacity of SDMs to predict the range expansion pattern of six free-living deer species in Great Britain and to assess whether SDMs perform better than a simple dispersal model - a null model that assumes no environmental control in the expansion process. Distribution data for the species prior to 1972 were used to train the SDMs (ENFA, MAXENT, logistic regression and an ensemble model) in order to obtain suitability maps. Additionally, the geographical distance to the localities occupied in 1972 was considered a proxy of the probability that a certain locality has to be occupied during an expansion process considering only dispersal (GD model). Subsequently, we analysed whether the species increased their ranges between 1972 and 2006 according to the estimated suitability patterns and whether or not SDMs predictions outperformed GD predictions. SDMs showed a high discrimination capacity in the training data, with the ensemble models performing the best and ENFA models the worst. SDMs predictions also worked better than chance in classifying new occupied localities, although differences among techniques disappeared and the predictions showed no difference with respect to GD. Spatial autocorrelation of both the environmental predictors and the expansion process may explain these results which illustrate that GD is a much more parsimonious model than any of the SDMs and may thus be preferable both for prediction and explanation. Overestimation of SDMs pe

[Aim]: When faced with dichotomous events, such as the presence or absence of a species, discrimination capacity (the ability to separate the instances of presence from the instances of absence) is usually the only characteristic that is assessed in the evaluation of the performance of predictive models. Although neglected, calibration or reliability (how well the estimated probability of presence represents the observed proportion of presences) is another aspect of the performance of predictive models that provides important information. In this study, we explore how changes in the distribution of the probability of presence make discrimination capacity a context-dependent characteristic of models. For the first time, we explain the implications that ignoring the context dependence of discrimination can have in the interpretation of species distribution models. [Innovation]: In this paper we corroborate that, under a uniform distribution of the estimated probability of presence, a well-calibrated model will not attain high discrimination power and the value of the area under the curve will be 0.83. Under non-uniform distributions of the probability of presence, simulations show that a well-calibrated model can attain a broad range of discrimination values. These results illustrate that discrimination is a context-dependent property, i.e. it gives information about the performance of a certain algorithm in a certain data population. [Main conclusions]: In species distribution modelling, the discrimination capacity of a model is only meaningful for a certain species in a given geographic area and temporal snapshot. This is because the representativeness of the environmental domain changes with the geographical and temporal context, which unavoidably entails changes in the distribution of the probability of presence. Comparative studies that intend to generalize their results only based on the discrimination capacity of models may not be broadly extrapolated. Assessme

In this paper we describe a new type of subterranean habitat associated with dry watercourses in the Eastern Iberian Peninsula, the “Alluvial Mesovoid Shallow Substratum” (alluvial MSS). Historical observations and data from field sampling specially designed to study MSS fauna in the streambeds of temporary watercourses support the description of this new habitat. To conduct the sampling, 16 subterranean sampling devices were placed in a region of Eastern Spain. The traps were operated for 12 months and temperature and relative humidity data were recorded to characterise the habitat. A large number of species was captured, many of which belonged to the arthropod group, with marked hygrophilous, geophilic, lucifugous and mesothermal habits. In addition, there was also a substantial number of species showing markedly ripicolous traits. The results confirm that the network of spaces which forms in alluvial deposits of temporary watercourses merits the category of habitat, and here we propose the name of “alluvial MSS”. The “alluvial MSS” may be covered or not by a layer of soil, is extremely damp, provides a buffer against above ground temperatures and is aphotic. In addition, compared to other types of MSS, it is a very unstable habitat. It is possible that the “alluvial MSS” may be found in other areas of the world with strongly seasonal climatic regimes, and could play an important role as a biogeographic corridor and as a refuge from climatic changes.

[Aim]: The extent of the study area (geographical background, GB) can strongly affect the results of species distribution models (SDMs), but as yet we lack objective and practicable criteria for delimiting the appropriate GB. We propose an approach to this problem using trend surface analysis (TSA) and provide an assessment of the effects of varying GB extent on the performance of SDMs for four species. [Location]: Mainland Spain. [Methods]: Using data for four well known wild ungulate species and different GBs delimited with a TSA, we assessed the effects of GB extent on the predictive performance of SDMs: specifically on model calibration (Miller's statistic) and discrimination (area under the curve of the receiver operating characteristic plot, AUC; sensitivity and specificity), and on the tendency of the models to predict environmental potential when they are projected beyond their training area. [Results]: In the training area, discrimination significantly increased and calibration decreased as the GB was enlarged. In contrast, as GB was enlarged, both discriminatory power and calibration decreased when assessed in the core area of the species distributions. When models trained using small GBs were projected beyond their training area, they showed a tendency to predict higher environmental potential for the species than those models trained using large GBs. [Main conclusions]: By restricting GB extent using a geographical criterion, model performance in the core area of the species distribution can be significantly improved. Large GBs make models demonstrate high discriminatory power but are barely informative. By delimiting GB using a geographical criterion, the effect of historical events on model parameterization may be reduced. Thus purely environmental models are obtained that, when projected onto a new scenario, depict the potential distribution of the species. We therefore recommend the use of TSA in geographically delimiting the GB for use in SDMs.

Parapatry is a biogeographical term used to refer to organisms whose ranges do not overlap, but are immediately adjacent to each other; they only co-occur - if at all - in a narrow contact zone. Often there are no environmental barriers in the contact zones, hence competitive interaction is usually advocated as the factor that modulates species distribution ranges. Even though the effects of climate change on species distribution have been widely studied, few studies have explored these effects on the biogeographical relationships between closely related, parapatric, species. We modelled environmental favourability for three parapatric hare species in Europe - Lepus granatensis, L. europaeus and L. timidus - using ecogeographical variables and projected the models into the future according to the IPCC A2 emissions scenario. Favourabilities for present and future scenarios were combined using fuzzy logic with the following aims: (i) to determine the biogeographical relationships between hare species in parapatry, that is L. granatensis/L. europaeus and L. europaeus/L. timidus and (ii) to assess the effects of climate change on each species as well as on their interspecific interactions. In their contact area L. granatensis achieved higher favourability values than L. europaeus, suggesting that if both species have a similar population status, the former species may have some advantages over the latter if competitive relationships are established. Climate change had the most striking effect on the distribution of L. timidus, especially when interspecific interactions with L. europaeus were taken into account, which may compromise the co-existence of L. timidus. The results of this study are relevant not only for understanding the distribution patterns of the hares studied and the effects of climate change on these patterns, but also for improving the general application of species distribution models to the prediction of the effects of climate change on biodiversity.

[EN]: We analysed the status of the taxonomical knowledge on Afrotropical and Palaearctic Eupelmidae (Hymenoptera, Chalcidoidea), by assessing the historical accumulation of valid new species and synonyms through time, as well as the factors that have determined the process of description of good species and synonyms in these regions. The species accumulation curves for valid species names show that a significant proportion of the taxa remains to be described in both areas. On the contrary, the historical accumulation of synonymic names seems to reach an asymptote in both areas, although the proportion of synonyms compared with the total number of names is higher in the Palaearctic region. We assessed factors influencing the probability of a species being discovered and the probability of being described several times under different names. Both probabilities seem to be affected by the same factors. Distribution range size and geographical location of taxa affect both the processes of discovering good species and producing synonyms in either region. Models using all these predictors explain (1) 36% and 40% of the variance in the year of description of valid names for the Afrotropical and Palaearctic regions respectively, and (2) 56% and 40% of the variation in the number of synonyms per valid species in these two areas. For the species with available information, trophic specialization is also a significant determinant of these probabilities. However, its effect is also accounted for by geographical range size, which can thus be used as a surrogate of the ecological correlates of discovery and redundant description probabilities. In general, the ecologically generalist, widely distributed and early described taxa living in northern and western areas of both regions have been subject of redundant description more times. Further, taxonomical effort is needed in the south and east of the Palaearctic, as well as in the whole of the Afrotropics, where additional effort i, [ES]: Se analiza el estado del conocimiento taxonómico sobre los Eupelmidae (Hymenoptera, Chalcidoidea) afrotropicales y paleárticos, mediante la evaluación de la acumulación histórica de nuevas especies válidas y sinónimos (descripciones redundantes de taxones previamente conocidos), así como los factores que han determinado el proceso de descripción de buenas especies y sinónimos en ambas regiones. Las curvas históricas de acumulación de especies válidas muestran que una proporción significativa de especies permanece sin describir en ambas áreas. Por el contrario, la acumulación histórica de sinónimos parece haber alcanzado una asíntota en las dos regiones, aunque la proporción de sinónimos sobre el total de nombres utilizados es mayor en la región paleártica. Se analizan también los factores que influyen en la probabilidad de que una especie sea descubierta y en la probabilidad de que sea redundantemente descrita varias veces, produciendo sinónimos. Ambas probabilidades parecen estar afectadas por los mismos factores. El tamaño del área de distribución y la localización geográfica de las taxones afecta tanto al proceso de descubrimiento de especies válidas como a la producción de sinónimos en ambas regiones. Los modelos construidos usando las citadas variables predictoras explican (i) el 36 y 40% de la varianza en el año de descripción de nombres válidos en las regiones afrotropical y paleártica, respectivamente, y (ii) el 56 y 40% de la varianza en el número de sinónimos por especie válida en esas dos regiones. Para las especies con información disponible, el grado de especialización trófica es también un determinante significativo de dichas probabilidades. Sin embargo, el tamaño del rango de distribución da cuenta del efecto de estas variables, por lo que puede ser utilizado como un indicador de los determinantes ecológicos de las tasas de descripción. En general, las especies generalistas, de amplia distribución y descritas más antiguamente que viven en las re

[ES] Se actualiza el listado de especies de las familias Araneidae y Thomisidae de la Comunidad de Madrid, citando 3 especies nuevas de araneidos y 15 de tomísidos, con lo que el número de especies de la primera familia asciende a 30 y a 43 el de la segunda. Se eliminan del catálogo Heriaeus hirtus y Larinioides cornutus. Tras elaborar los mapas de distribución conocida y potencial se constata una falta de datos corológicos, especialmente acusado en la familia Thomisidae debido a su carácter críptico. Los mapas de riqueza específica reflejan un patrón común, con valores máximos de riqueza en la Rampa y valores mínimos en el sur de la Comunidad y en las zonas de alta montaña. Aunque los valores brutos de riqueza sean, seguramente, una subestimación de los valores reales, el patrón general puede ser explicado en base a las preferencias ecológicas de las dos familias y al patrón espacial de la alteración antrópica del hábitat en la provincia de Madrid. Se resalta la necesidad urgente de efectuar muestreos para completar los grandes huecos de información., [EN] The list of species of the families Araneidae and Thomisidae in Comunidad de Madrid is updated. 3 new species of Araneidae and 15 of Thomisidae are added to the list, for a total of 30 species in the first family, and of 46 in the second. Heriaeus hirtus and Larinioides cornutus are eliminated from the catalogue. After the distributional and predictive maps were drawn, an significant lack of distributional records is noticed, especially in the Thomisidae due, probably, to their cryptic nature. Richness maps show a common pattern, with maximum values in the Rampa and minimum ones in the south of the province and high altitudes of the Sierra. Although richness scores are probably a sub estimation of true values, the general pattern can be explained according to the ecological preferences of the two families and the spatial pattern of anthropogenic alteration of the habitat in Madrid. The imperative necessity of making field surveys to complete data gaps is highlighted.

Diversity patterns of the butterfly fauna of the Parque Nacional de Cabañeros and its surroundings (Ciudad Real, Central Spain) (Lepidoptera, Papilionoidea, Hesperioidea).� The butterfly species richness and faunistic composition in six plots with different land uses and dissimilar environmental diversity is studied in the Parque Nacional de Cabañeros and its surroundings (Ciudad Real, Central Spain). The holm�oak forest is the richest sampling plot, with a butterfly species composition that clearly differs from the rest of more humanized sampling plots. The pine plantation has the lowest values of species richness and abundances, with a faunistic composition quite similar to those of the sampling plots with a dominance of hostile habitats for butterflies (grasslands and crops), so the need to create clearings is emphasised. The importance of environmental diversity in humanized habitats and the need for proper management and conservation of woodlands is stressed in order to conserve butterfly biodiversity., Patrones de diversidad de la fauna de mariposas del Parque Nacional de Cabañeros y su entorno (Ciudad Real, España central) (Lepidoptera, Papilionoidea, Hesperioidea).� Se estudia la riqueza en especies de mariposas y la composición faunística en seis parcelas representativas de distintos usos del monte mediterráneo y con distinto valor de diversidad ambiental, en el Parque Nacional de Cabañeros y su entorno (Ciudad Real, España central). La parcela representativa del bosque mediterráneo resulta ser la más rica en mariposas y presenta una composición faunística que la diferencia claramente del resto de parcelas con mayor grado de antropización. La parcela representativa de la plantación de coníferas es la más pobre en cuanto a número de especies e individuos, y su composición faunística la asemejan a las parcelas más hostiles para las mariposas, como son las parcelas con dominancia de zonas para pastos y agrícolas. Por ello, se recalca la necesidad de crear espacios aclarados para mejorar estas masas arbóreas y hacerlas más atractivas para la fauna lepidopterológica. Se pone en relevancia la importancia de la diversidad ambiental en los hábitats antropizados y la necesidad de una gestión y conservación adecuadas de zonas boscosas de cara a mantener la biodiversidad lepidopterológica.