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Aim To assess the effectiveness of protected area networks in representing the climatic niche of Iberian water beetle species. Location Iberian Peninsula. Methods We used distribution data from 133 endemic water beetle species in the Iberian Peninsula. Climatic potential distributions were estimated by applying a multidimensional-envelope procedure based on climatic data (both current and future) and observed occurrences. Mahalanobis distances were calculated to obtain continuous climatic suitability values within the climatic potential distribution. Two protected area networks were assessed: National Parks ( NPs) and Natura 2000 ( N2000). The average climatic suitability value for the cells overlapping with protected areas was calculated and compared with the average value of 10,000 random samples from the same number of cells within their entire potential distribution, which allowed to identify species whose climatic niches were optimally or marginally represented. Results Fifty-seven and 104 of the 107 considered taxa were represented with at least one occurrence in NPs and N2000, respectively, and the climatic potential distributions of 93 and all 107 taxa overlapped with NPs and N2000. While the climatic niches of 48 and 38 taxa were marginally represented in NPs and N2000, the climatic niches of only 11 and 29 were optimally represented by these two protected area networks. When predicted future climatic conditions were considered, both the climatic suitability values and the number of species whose potential distribution was represented by protected areas decreased. Main conclusions Although the representation of endemic Iberian taxa could be considered adequate, these results show that for most of them the protected networks tend to include areas with climatic conditions close to the species tolerance limit, and the expected climate change only worsened this scenario. Thus, current protected areas cannot be considered to guarantee the long-term survival of the species considered in this study. [ABSTRACT FROM AUTHOR]

Highlights: [•] Iberian National Parks (NPs) perform poorly in the preservation of freshwater phylogenetic diversity (PD). [•] Often PD in NPs was not different from random, and sometimes lower than expected. [•] Most of the highly evolutionarily distinct and vulnerable taxa were not covered by NPs. [•] High variation in covered PD when additional areas selected maximizing species richness. [ABSTRACT FROM AUTHOR]

A basic aim of ecology is to understand the determinants of organismal distribution, the niche concept and species distribution models providing key frameworks to approach the problem. As temperature is one of the most important factors affecting species distribution, the estimation of thermal limits is crucially important for inferring range constraints. It is expectable that thermal physiology data derived from laboratory experiments and species' occurrences may express different aspects of the species' niche. However, there is no study systematically testing this prediction in a given taxonomic group while controlling by potential phylogenetic inertia. We estimate the thermal niches of twelve Palaearctic diving beetles species using physiological data derived from experimental analyses in order to examine the extent to which these coincided with those estimated from distribution models based on observed occurrences. We found that thermal niche estimates derived from both approaches lack general congruence, and these results were similar before and after controlling by phylogeny. The congruence between potential distributions obtained from the two different procedures was also explored, and we found again that the percentage of agreement were not very high (~60%). We confirm that both thermal niche estimates derived from geographical and physiological data are likely to misrepresent the true range of climatic variation that these diving beetles are able to tolerate, and so these procedures could be considered as incomplete but complementary estimations of an inaccessible reality. [ABSTRACT FROM AUTHOR]

Ongoing global climate change presents serious challenges in conservation biology, forcing us to revisit previous tools and principles based on how species may respond to novel climatic conditions. There is currently a major gap between predictions of species vulnerability and management strategies, despite the fact that linking these areas is fundamental for future biodiversity conservation. Herein, we evaluate what drives vulnerability to climate change in three Iberian endemic water beetles, representing three independent colonizations of the same habitat, employing comparative thermal physiology, species distribution models and estimations of species dispersal capacity. We derive conservation strategies for each species based on their differential capacity to persist and/or potential to shift their ranges in response to global warming. We demonstrate that species may be affected by climatic warming in very different ways, despite having broadly similar ecological and biogeographical traits. The proposed framework provides an effective complement to traditional species vulnerability assessments, and could aid the development of more effective conservation strategies in the face of global warming. [ABSTRACT FROM AUTHOR]

Aim In aquatic ecosystems, standing (lentic) and running (lotic) waters differ fundamentally in their stability and persistence, shaping the comparative population genetic structure, geographical range size and speciation rates of lentic versus lotic lineages. While the drivers of this pattern remain incompletely understood, the suite of traits making up the ability of a species to establish new populations is instrumental in determining such differences. Here we explore the degree to which the association between habitat type and geographical range size results from differences in dispersal ability or fundamental niche breadth in the members of the Enochrus bicolor complex, an aquatic beetle clade with species across the lentic-lotic divide. Location Western Mediterranean, with a special focus on North Africa, the Iberian Peninsula and Sicily. Methods DNA sequences for four loci were obtained from species of the E. bicolor complex and analysed using phylogenetic inference. Dispersal and establishment abilities were assessed in lentic-lotic species pairs of the complex, using flight wing morphometrics and thermal tolerance ranges as surrogates, respectively. Results There were clear differences in range size between the lotic and lentic taxa of the complex, which appears to have had a lotic origin with two transitions to standing waters. Only small differences were observed in temperature tolerance and acclimation ability between the two lotic-lentic sister species studied. By contrast, wing morphometrics revealed clear, consistent differences between lotic and lentic Enochrus species pairs, the latter having a higher dispersal capacity. Main conclusions We hypothesize that there have been two habitat shifts from lotic to lentic waters, which have allowed marked expansions in geographical range size in western Mediterranean species of the E. bicolor complex. Differences in dispersal rather than in establishment ability appear to underlie differences in geographical range extent, as transitions to lentic waters were associated with changes in wing morphology, but not in thermal tolerance range. In this lineage of water beetles, selection for dispersal in geologically short-lived lentic systems has driven the evolution of larger range sizes in lentic taxa compared with those of their lotic relatives. [ABSTRACT FROM AUTHOR]

. 1. Nowadays, it is widely accepted that increasing human activity is highly related to the current biodiversity loss, this fact being especially worrying in aquatic ecosystems, mainly in semi-arid areas. To date, studies on the biodiversity of small standing waters are focused on Central and Northern Europe, Mediterranean regions being poorly documented. 2. Here, data for aquatic Coleoptera in SE Iberia have been used to: (i) explore the relative contribution of standing waters to regional aquatic biodiversity, (ii) identify the environmental drivers structuring beetle assemblages, (iii) determine the degree to which standing water assemblages are nested subsets, and (iv) make recommendations for the conservation and management of the habitats studied. 3. Water beetles are a hyperdiverse group of aquatic insects which represent good surrogates of aquatic biodiversity. A total of 95 sites across eight habitat types were sampled, 174 species being recorded (11% were Iberian endemics). 4. Habitat types generally had distinct aquatic beetle faunas; a combination of conductivity, anthropogenic impact and altitude best explaining differences in assemblages across sites. Beetle faunas were significantly nested, this being the case across all sites, and for both fresh and saline systems independently. Disturbance was identified as a key driver of nestedness across sites overall, and particularly in freshwaters, whereas conductivity was more important in saline waters. 5. Our study identifies the biodiversity importance of lentic inland waters in the Iberian southeast, and points to the influence that human activities already exert on the invertebrate faunas of western Mediterranean wetlands. [ABSTRACT FROM AUTHOR]

Abstract: Good distribution maps based on adequate sampling of a number of taxonomic groups are required to provide reliable conservation strategies. Nevertheless, it is common that inventories of many animal groups, particularly insects, are incomplete or nonexistent, with large gaps appearing once all available information of insects is mapped, especially when wide spatial scales are considered. Due to the lack of resources and manpower, the accomplishment of future field campaigns in these generally poorly surveyed areas should be directed so as to maximise the information obtained with the minimum survey effort. Using an exhaustive database of Iberian water beetles (which was relatively scarce and biased), we aim to prioritise areas to propose a planned survey design able to generate more accurate geographical representations of species distributions. For this, a prediction on the geographic distribution of the species richness of this group in the Iberian Peninsula was first obtained using the information coming from seven sets of well-surveyed grid cells determined by using progressively more exigent completeness values. Both observed and estimated by accumulation curves, species richness values of these different cell groups were subsequently used as the dependent variable in the modelling procedure. We used generalised linear models and 18 environmental variables as predictors. In this manner, 14 species richness predictions were obtained whose predictive power was assessed by a Jackknife procedure. The best model explained 57.5% of total deviance with a high mean Jackknife predictive error (29.9%). The overlay of these predictions with the survey effort map allows us to locate those areas where more sampling effort is necessary (areas of high predicted species richness that are not well inventoried). [ABSTRACT FROM AUTHOR]

One of the most serious environmental problems is the current acceleration in the rate of species extinction associated with human activities, which is occurring particularly rapidly in freshwaters. Here we examine whether endemic water beetles are effectively protected by existing conservation measures in the Iberian Peninsula and the Balearic Islands, a region of high diversity and intense human pressure. We used an exhaustive database for aquatic beetles in the region to address such issues. Firstly, we identify the most threatened endemic taxa using a categorization system to rank species according to their conservation priority or vulnerability. Of the 120 endemic species of water beetles used in the analysis, only two (Ochthebius ferroi and Ochthebius javieri) were identified as being extremely vulnerable, 71 were highly vulnerable and 46 moderately vulnerable, with only a single species identified as having low vulnerability status. Since no Iberian species of aquatic Coleoptera has legal protection, the only conservation measure available for these species is the extent to which they occur in protected areas. Here we identify distributional hotspots for threatened endemic species, and evaluate the extent to which these are already included in the Natura 2000 network in Spain and Portugal. Despite a high degree of concordance between hotspots and Natura 2000 sites, the distribution of four species falls completely outside the network. The analysis also reveals that Natura 2000 fails to protect saline water bodies, despite their high conservation interest and narrow global distribution. The picture revealed here with water beetles is likely to be similar for others groups of freshwater macroinvertebrates, since Coleoptera are known to be good surrogates of aquatic biodiversity in the region. Finally, the degree of protection provided via Natura 2000, and the utility of red lists are discussed. [Copyright &y& Elsevier]

1. Biodiversity is probably at greater risk in freshwater systems than in other ecosystems. Although protected areas (PAs) play a vital role in the protection of biodiversity and are the mainstay of most conservation polices, the coverage of biodiversity by existing PA networks is often inadequate and few reserves are created that take into consideration freshwater biota. 2. In this paper an attempt is made to address the performance of protected areas in the context of freshwater biodiversity conservation using data records for water beetles in a Mediterranean river basin. 3. Although the present PAs in the study area cover a relatively high number of water beetle species, the distribution and extent of reserves is still inadequate or insufficient to protect freshwater biodiversity, especially species of conservation concern. 4. Alternative area-selection methods (hotspots and complementary) were more efficient than PAs for representing water beetles. Within these, complementarity was the most efficient approach, and was able to represent all species in a significantly lower area than the current PA network. On the other hand, the future Natura 2000 Network will result in a great increase in the total area of protected land as well as in the biodiversity represented. 5. Unfortunately, the occurrence of a species within a protected area is not a guarantee of long-term survival because the extent of PAs is often insufficient and disturbances occur outside park boundaries. Thus, whole-catchment management and natural-flow maintenance are indispensable strategies for freshwater biodiversity conservation. [ABSTRACT FROM AUTHOR]

We propose an objective method for assessing the vulnerability of species and for prioritizing species and populations for conservation, especially insects. Species of water beetles from two Spanish provinces of the southeast of the Iberian Peninsula were ranked according to their conservation priority at the local, national and global levels taking into consideration a set of six variables: general distribution, endemicity, rarity, persistence, habitat rarity and habitat loss. Each variable was categorized into four ranks (0–3) of increasing risk for survival. Ochthebius glaber, Ochthebius irenae, Ochthebius montesi, Ochthebius albacetinus and Hydraena mecai were seen to be the most vulnerable, for which reason we propose they should be included in the national red list. Furthermore, O. glaber, O. irenae and O. montesi are proposed for inclusion in the IUCN red list as “Vulnerable”. These species are Iberian endemisms, with geographic ranges restricted to the southeast, and are threatened by habitat loss. Effective protection of these species requires measures directed at the conservation of their habitats. Crucial target habitats for protection in the southeast of the Iberian Peninsula include freshwater streams at medium altitudes, saline streams and endorreic lagoons. [Copyright &y& Elsevier]