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1.
This study analyzes the somatic condition of southern Iberian barbel Luciobarbus sclateri (Günther, 1868) in the Guadiamar River (SW Iberian Peninsula). This river was seriously affected by a toxic spill of about 4?million cubic meters of acidic water and 2?million cubic meters of mud rich in heavy metals. Once the spill removal works concluded, sites affected and unaffected by the accident were sampled to study its effects on the fish fauna. The ecological variables registered were related to water quality, physical state of reaches, ecological quality, resources exploited by fish, and potential intra-specific interactions. From an initial 15 ecological variables, seasonal water flow and pH explained most of the variation in barbel condition. This study shows that the Guadiamar River, 56?months after the accident, is still undergoing a recovery process where, beyond ecological variables, proximity to the affected area is the most influential factor for fish condition.  相似文献   

2.
This study is part of the Restoration Program of the animal populations from the Guadiamar River basin. The main objective is to evaluate the current state of populations of the most representative groups of edaphic coleoptera in the Guadiamar River basin. In 1998, a breach in the Aznalcóllar mines retaining wall (Southern Iberian Peninsula) led to toxic sludge pouring out into this area. Systematic samples were taken from monitoring plots, scattered throughout the affected area. In order to provide an overall assessment of the fauna collected from this area in relation to adjacent areas, ecological indices were applied, and temporal course and biogeographical comparisons were also made. The results indicate that, overall, the edaphic fauna has not been significantly affected by the spillage; however, a faunistic poverty was also detected, which becomes increasingly evident closer to the accident site. Moreover, temporal evolution analysis suggests that the most affected areas are undergoing a re-colonization process, although this varies widely between species and higher taxa. This research has been financed by the Project ‘Caracterización, restauración y conservación de las comunidades animales de la cuenca del río Guadiamar’ (Characterization, Re-establishment and Conservation of the animal communities from the Guadiamar River basin). Consejería de Medio Ambiente. Junta de Andalucía (Spain).  相似文献   

3.
Abstract. A study to assess the influence of abiotic (climatic conditions) and biotic factors (food resources, habitat preference and human activity) on endemism patterns of dung beetles in the Mediterranean region was conducted in the Iberian Peninsula and the Balearic Islands. The Thermicity Index (It), the Mediterraneity Index (Im3) and the Aridity Index (Ia) were used to assess the influence of abiotic factors. Relative rabbit density (DR), the proportion of landscape used historically for grazing by sheep and goats and the nature of the food resource were used to assess the influence of biotic factors. Relative endemism (EN) of dung beetle assemblages was positively and significantly related with all of the factors considered. However, the Aridity and Mediterraneity Indices are the best predictors of EN. The predicted endemism (EN = 0.017 Ia + 0.004 Im3 + 0.422) was highly positively and significantly related with the observed endemism. Dung beetle assemblages with the highest relative endemism were observed in the south-eastern part of the Iberian Peninsula. This distribution corresponded to the highest Aridity and Mediterraneity. In contrast, dung beetle assemblages with lower endemism were located in more humid and temperate areas. Assemblages of dung beetles with the highest endemism comprise many species adapted to aridity and the exploitation of dry dung pellets. Conservation of traditional grazing activity by pellet-dropping sheep and goats might benefit the maintenance of dung beetle biodiversity in Mediterranean ecosystems.  相似文献   

4.
The earth-boring dung beetles belong to the family Geotrupidae that includes more than 350 species classified into three subfamilies Geotrupinae, Lethrinae, and Taurocerastinae, mainly distributed across temperate regions. Phylogenetic relationships within the family are based exclusively on morphology and remain controversial. In the Iberian Peninsula there are 33 species, 20 of them endemic, which suggests that these lineages might have experienced a radiation event. The evolution of morphological adaptations to the Iberian semi-arid environments such as the loss of wings (apterism) or the ability to exploit alternative food resources is thought to have promoted diversification. Here, we present a phylogenetic analysis of 31 species of Geotrupidae, 17 endemic to the Iberian Peninsula, and the remaining from southeastern Europe, Morocco, and Austral South America based on partial mitochondrial and nuclear gene sequence data. The reconstructed maximum likelihood and Bayesian inference phylogenies recovered Geotrupinae and Lethrinae as sister groups to the exclusion of Taurocerastinae. Monophyly of the analyzed geotrupid genera was supported but phylogenetic relationships among genera were poorly resolved. Ancestral character-state reconstruction of wing loss evolution, dating, and diversification tests altogether showed neither evidence of a burst of cladogenesis of the Iberian Peninsula group nor an association between apterism and higher diversification rates. Loss of flight did not accelerate speciation rates but it was likely responsible for the high levels of endemism of Iberian geotrupids by preventing their expansion to central Europe. These Iberian flightless beetle lineages are probably paleoendemics that have survived since the Tertiary in this refuge area during Plio-Pleistocene climatic fluctuations by evolving adaptations to arid and semi-arid environments.  相似文献   

5.
Aims This study explores the patterns of niche differentiation in a group of seven closely related columbines (genus Aquilegia, Ranunculaceae) from the Iberian Peninsula. Populations of these columbines are subject to complex patterns of divergent selection across environments, which partly explain the taxonomic structure of the group. This suggests the hypothesis that niche divergence must have occurred along the process of diversification of the group.Methods We used MaxEnt to build environmental niche models of seven subspecies belonging to the three species of Aquilegia present in the Iberian Peninsula. From these models, we compared the environmental niches through two different approaches: ENMtools and multivariate methods.Important findings MaxEnt distributions conformed closely to the actual distribution of the study taxa. ENMtools methods failed to uncover any clear patterns of niche differentiation or conservatism in Iberian columbines. Multivariate analyses indicate the existence of differentiation along altitudinal gradients and along a gradient of climatic conditions determined by the summer precipitation and temperatures. However, climatic conditions related to winter temperature and precipitation, as well as soil properties, were equally likely to show conservatism or divergence. The complex patterns of niche evolution we found suggest that Iberian Columbines have not been significantly constrained by forces of niche conservatism, so they could respond adaptively to the fast and profound climate changes in the Iberian Peninsula through the glacial cycles of the Pleistocene.  相似文献   

6.
High morphological and ecological diversity has been observed in the north-west Iberian Peninsula endemic Anthoxanthum amarum Brot., for which two different morphotypes (northern and southern) have been described on the basis of qualitative traits and geographical origin. In the present study, a combined molecular and morphological method was applied to ten populations of this species with the following aims: (1) to assess whether the variation observed was taxonomically meaningful; (2) to assess the influence of the environment on the variation in the morphological characters; and (3) to track the potential phylogeographical information deduced from our random amplified polymorphic DNA marker (RAPD) data in order to draw inferences about the past history of this species in the north-west Iberian Peninsula. To achieve these aims, 26 macromorphological characters were recorded in 279 specimens, and 77 RAPD phenotypes were identified in the 79 plants studied. The association analyses performed using the morphological and molecular data showed that no clear separation existed between the morphs, and a strong correlation between qualitative characters and the environment was detected. Moreover, both the multivariate analyses and the assignment test based on RAPD data revealed that the genetic variation was hierarchically structured, and three genetically distinct groups could be identified. Two of these clusters might correspond to different expansion routes proposed in the literature for different plant species in the north-west Iberian Peninsula.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 179–192.  相似文献   

7.
The Timarcha goettingensis complex is a monophyletic assemblage of closely related leaf beetles (Chrysomelidae), distributed from the north half of the Iberian Peninsula to Central Europe. Oligophagy, mountainous habitat and apterism are factors which are assumed to promote speciation in these beetles. We have used cytochrome oxidase subunit II mitochondrial DNA genealogies obtained from 31 sampling localities and a nested geographical distance analysis to assess the population structure and demographic factors explaining the geographical distributions of the mtDNA haplotypes in the T. goettingensis complex. The results show that there is a significant association between genetic structuring and geography. Inferences about the historical population processes in the species complex are discussed, being in general in accordance with contiguous range expansions and past fragmentations. The use of the cohesion species concept approach suggests the existence of several systematic ranks among the different T. goettingensis populations, which is in part supported by ecological traits such as trophic selection and altitudinal distribution.  相似文献   

8.
A phylogeny of the main lineages of dung beetles (Coleoptera: Scarabaeinae) from the Iberian Peninsula was based on partial nucleotide sequences (about 1221 bp) of the mitochondrial cytochrome oxidase I and II genes of 33 taxa. Our phylogenetic analyses confirmed the validity and composition of most of the recognized tribes within the subfamily. Interestingly, the Onitini showed an evolutionary rate significantly higher than that of the other tribes. The molecular phylogeny supports a sister-group relationship of the tribes Onitini and Oniticellini + Onthophagini. A close relationship of Scarabaeini, Gymnopleurini, and Sisyphini is also suggested but lacks bootstrap support. Surprisingly, the Coprini, which had always been related to the Oniticellini and Onthophagini, were placed closer to the Scarabaeini, Gymnopleurini, and Sisyphini. The inferred molecular phylogeny was used to assess the main evolutionary trends of nesting behavior. Our results suggest tentative single origins for both the tunneling and the rolling behaviors, and the possibility that the rolling behavior could have been lost secondarily in Copris.  相似文献   

9.
Aim  The aim of this work was to identify the main changes in the flora and vegetation of the Iberian Peninsula over the Cenozoic Era, to record the disappearance of taxa associated with these changes and to determine the influence of climate and human activity on these events.
Location  The Iberian Peninsula and Balearic Islands.
Methods  A critical review was made of the palaeobotanical literature with the aims of detecting patterns of floristic change and extracting information on the disappearance of different taxa over the Cenozoic. These data are viewed alongside the most recent data for the climate of this period. A critical analysis is made of the role of Palaeotropical and Arctotertiary taxa in the forest communities of the Iberian Peninsula throughout the Cenozoic.
Results  Although the Eocene–Oligocene transition was a time when many taxa disappeared, the most outstanding events occurred between the end of the Oligocene and throughout the Miocene. Substantial floristic changes took place over this period, including the disappearance of 177 Palaeotropical taxa. This was probably related to acute cooling and aridification; no evidence exists that the Messinian Salinity Crisis had any important effect in the Iberian Peninsula. The last great disappearance of Palaeotropical taxa (36 in total) ended in the Middle–Late Piacenzian; Arctotertiary taxa were most affected during the Pleistocene. The Lower–Middle Pleistocene transition, best represented by marine isotopic stages (MIS) 36–34 and 20–18 and characterized by a change in glacial cyclicity, was the time of the last notable disappearance of taxa.
Main conclusions  This work provides the first chronogram of extinctions for the Iberian flora, and records the disappearance of 277 taxa during the Cenozoic. A clear relationship was detected between the main climatic events and the latest appearances of the different taxa.  相似文献   

10.
Spinosaurids are one of the most abundant theropods from the Early Cretaceous of the Iberian Peninsula. The published fossil record consists mainly of teeth. A good example is La Cantalera-1 site in the Blesa Formation (Spain). This site represents a marshy environment with periodic droughts, resulting in a non-permanent body of water. Theropod dinosaur teeth are frequent. Seventeen spinosaurid teeth have been studied using qualitative and quantitative features, including a statistical analysis, in order to compare them with the known spinosaurid record from Spain. In La Cantalera-1 we recognise two different morphotypes: Baryonychinae indet. and Spinosaurinae? indet. Baryonychinae indet. was produced by baryonychines close to Baryonyx; teeth with similar morphology have been described in other sites from the Early Cretaceous of the Iberian Peninsula. Teeth tentatively attributed to Spinosaurinae? indet. were produced by spinosaurines close to Spinosaurus. This morphotype could provide new evidence of the presence of spinosaurines in the Early Cretaceous of the Iberian Peninsula. The small size of the teeth from La Cantalera-1 when compared with those from other sites is interpreted as the result of the conditions characteristic of the deposit area, which represents an ecosystem unable to sustain large-sized organisms.  相似文献   

11.
The phylogenetic relationships among 26 species of the subgenus Luciobarbus were examined through comparison of the complete sequence of the mitochondrial genes ATPase 6 and 8 and cytochrome b. The monophyletic condition of the Luciobarbus subgenus was confirmed by several data treatment methods. Findings indicate a closer relationship among species inhabiting Caucasian, Greek, and North African areas than between the latter and those of the Iberian region. The isolation of these main clades is postulated to have occurred after the Messinian salinity crisis (5.5 MY ago) when the Iberian Peninsula broke away from the African continent. Based on a calibrated molecular clock proposed herein, the subsequent splitting of this subgenus corresponds to the isolation of the other three areas (Caucasian, Greek, and North African) about 4.5 MY ago, which would have interrupted any possible gene flow between lineages. However, the present data indicate that the North African Kabilies Mountain area maintained its contact with the south Iberian Peninsula for a longer period.  相似文献   

12.
The Italian and Balkan peninsulas have been places traditionally highlighted as Pleistocene glacial refuges. The Iberian Peninsula, however, has been a focus of controversy between geobotanists and palaeobotanists as a result of its exclusion from this category on different occasions. In the current paper, we synthesise geological, molecular, palaeobotanical and geobotanical data that show the importance of the Iberian Peninsula in the Western Mediterranean as a refugium area. The presence of Aesculus aff. hippocastanum L. at the Iberian site at Cal Guardiola (Tarrasa, Barcelona, NE Spain) in the Lower–Middle Pleistocene transition helps to consolidate the remarkable role of the Iberian Peninsula in the survival of tertiary species during the Pleistocene. The palaeodistribution of the genus in Europe highlights a model of area abandonment for a widely-distributed species in the Miocene and Pliocene, leading to a diminished and fragmentary presence in the Pleistocene and Holocene on the southern Mediterranean peninsulas. Aesculus fossils are not uncommon within the series of Tertiary taxa. Many appear in the Pliocene and suffer a radical impoverishment in the Lower–Middle Pleistocene transition. Nonetheless some of these tertiary taxa persisted throughout the Pleistocene and Holocene up to the present in the Iberian Peninsula. Locating these refuge areas on the Peninsula is not an easy task, although areas characterised by a sustained level of humidity must have played an predominant role.  相似文献   

13.
Mediterranean countries like Portugal and Spain, so far characterised by extensive traditional land use over major parts of their territories, have been less affected by species losses. However, they are facing severe changes. As a model organism we chose the butterfly Euphydryas aurinia, highly threatened in Central Europe but still common at the Iberian Peninsula, for a mark-release-recapture survey in the western Algarve. We examined key factors for stabile metapopulation systems to assess the ability of long-term survival in the increasingly fragmented landscapes of the Iberian Peninsula. The density of the examined population was high (ca. 2,200 individuals/ha). However, the MRR-based proportion of individuals moving longer distance classes showed a better fit to the negative exponential function than to the inverse power function implying restricted dispersal behaviour. The orientation pattern of short distance movements (<10 m) proved to be independent from habitat structures. In contrast, longer movements (>10 m) were strongly orientated along the main habitat axes revealing the importance of internal habitat structures for the orientation of dispersing individuals. Based on these data, we discuss the severe consequences for the fauna of the Iberian Peninsula in an increasingly fragmented and monotonous landscape.  相似文献   

14.
Aim The aims of this paper are to examine diversity–variability patterns for species of Aphodiinae (Coleoptera, Scarabaeoidea, Aphodiidae) on the Iberian Peninsula, and to determine the factors that influence their geographic distribution. Location Iberian Peninsula (Spain and Portugal). Methods Data from 30 studies and their bibliographies on species of Iberian Peninsula Aphodiinae were compiled. The reliability of the inventories was evaluated using parametric species richness estimators. In addition, a further 11 variables related to rarity, geographic distribution, or phylogenetic diversity were considered. Diversity variables were analysed using principal components analysis to reduce the number of dependent variables. Subsequently, the effect of differences in locality size among the 30 studies was eliminated by calculating and retaining the residuals of the curvilinear relationship of each diversity variable with the area. Generalized linear models were used to examine the relationships between diversity and 17 environmental variables. The diversity variables and their residuals were also subject to trend surface analysis in order to identify the relevance of spatially structured variables that had not been considered. The contribution of explanatory variables was determined through hierarchical variance analysis. Results Principal components analysis of biodiversity variables revealed that most of the variability could be explained using three biodiversity indexes: BI1, correlated positively with species richness, widely distributed species, frequent species, abundant species, species occurring in North Africa, Europe and the Iberian Peninsula, and phylogenetic diversity; BI2, correlated positively with numbers of infrequent and African–Iberian species; and, BI3, correlated positively with numbers of endemic, non‐abundant, European, and Iberian‐restricted species. A latitudinal disjunction emerged in BI1, with maximum scores at the north‐western and southern corners, while maximum BI2 scores were found throughout the south, and maximum BI3 scores in the north‐west. For BI1, it was climate that had the greatest influence, followed by lithology, and livestock presence. Geographic variables were the most significant for BI2, followed by climate and livestock presence. Finally, for BI3, climate variables were the most important, while geography, lithology and livestock presence had some relevance. Main conclusions The relevance of geographic variables indicates that other unaccounted‐for factors that are spatially structured could possibly explain additional variation in Aphodiinae diversity. These factors may be historic in nature, relating to the species groups, namely the Ibero‐European and the Mediterranean or Afro‐Iberian. The northern pattern could reflect the fact that the Iberian Peninsula acted as a colonization route and as a refuge during the glacial/interglacial cycles, while the southern pattern could be a consequence of the connection between the Iberian Peninsula and North Africa during the Messinian crisis, and/or a historic relationship in common, related to human activity.  相似文献   

15.
The ESACIB (‘EScarabajos ACuáticos IBéricos’) database is provided, including all available distributional data of Iberian and Balearic water beetles from the literature up to 2013, as well as from museum and private collections, PhD theses, and other unpublished sources. The database contains 62,015 records with associated geographic data (10×10 km UTM squares) for 488 species and subspecies of water beetles, 120 of them endemic to the Iberian Peninsula and eight to the Balearic Islands. This database was used for the elaboration of the “Atlas de los Coleópteros Acuáticos de España Peninsular”. In this dataset data of 15 additional species has been added: 11 that occur in the Balearic Islands or mainland Portugal but not in peninsular Spain and an other four with mainly terrestrial habits within the genus Helophorus (for taxonomic coherence). The complete dataset is provided in Darwin Core Archive format.  相似文献   

16.
Southern European columbines (genus Aquilegia) are involved in active processes of diversification, and the Iberian Peninsula offers a privileged observatory to witness the process. Studies on Iberian columbines have provided significant advances on species diversification, but we still lack a complete perspective of the genetic diversification in the Iberian scenario. This work explores how genetic diversity of the genus Aquilegia is geographically structured across the Iberian Peninsula. We used Bayesian clustering methods, principal coordinates analyses, and NJ phenograms to assess the genetic relationships among 285 individuals from 62 locations and detect the main lineages. Genetic diversity of Iberian columbines consists of five geographically structured lineages, corresponding to different Iberian taxa. Differentiation among lineages shows particularly complex admixture patterns at Northeast and highly homogeneous toward Northwest and Southeast. This geographic genetic structure suggests the existence of incomplete lineage sorting and interspecific hybridization as could be expected in recent processes of diversification under the influence of quaternary postglacial migrations. This scenario is consistent with what is proposed by the most recent studies on European and Iberian columbines, which point to geographic isolation and divergent selection by habitat specialization as the main diversification drivers of the Iberian Aquilegia complex.  相似文献   

17.
Eurylophella iberica Keffermüller and Da Terra, 1978 is an endemic insect species of the Iberian Peninsula whose distribution has been poorly studied to date with rather old and scattered records. Here we compiled all existing distribution records and add new records from recent sampling activities. We also used this updated distributional information and environmental data (climate and geology) to estimate both current and future potential distributions in different climate change scenarios. We found that currently ca. 50% of the total Iberian region could present suitable environmental conditions for E. iberica (all the Iberian Peninsula, save the most eastern and Mediterranean areas). However, the potential distributions estimated when considering future climate change scenarios showed a marked reduction in the areas with suitable environmental conditions for the species, especially in the south. The northwest part of the Iberian Peninsula is a crucial zone for the future survival of this endemic species. We also found that most populations that occur in areas with suitable (both current and future) environmental conditions fall outside the Natura 2000 network of protected areas. Our results represent the first attempt to estimate the potential distribution of this endemic species providing important insights for its conservation.  相似文献   

18.
This study investigated the phylogeographic structure of Cistus ladanifer, in order to locate its Quaternary refugia, reconstruct its recolonisation patterns and assess the role of geographical features (mountain ranges, rivers and the Strait of Gibraltar) as barriers to its seed flow and expansion through the Western Mediterranean. Thirty-eight populations were screened for length variation of polymorphic chloroplast simple sequence repeats (cpSSRs). Statistical analyses included estimation of haplotypic diversity, hierarchical analysis of molecular variation (amova) and fixation indices. Mantel tests, SAMOVA and BARRIER analyses were applied to evaluate the geographical partitioning of genetic diversity across the entire species range. Pollen data from bibliography were used to complement molecular inferences. Chlorotype diversity within populations was similar throughout the natural range of C. ladanifer (mean haplotypic diversity=0.32). High differentiation among populations was estimated (G(ST)=0.60). Our data suggest that the barriers of the Strait of Gibraltar and the Betic ranges may have favoured the divergence during glacial periods of four different lineages of populations inferred with SAMOVA. The main northward colonisation of in the Iberian Peninsula occurred from refugia in southwest Iberia. This process may have been influenced by human activities (forest clearance, livestock grazing and even commerce) in the Iberian Peninsula. In contrast, populations in the Betic area have conserved a specific haplotype.  相似文献   

19.
The Formicidae are considered crucial components of the entomosarcosaprophagous fauna because they can delay the decomposition process, cause tissue postmortem damage and produce bloodstain patterns that may confuse investigations. Moreover, some studies suggest that the Formicidae can act as environmental and seasonal indicators. However, studies on this group on vertebrate carcasses are scarce, especially in the Iberian Peninsula and the southwest of Europe. Thus, comparative studies at different altitudes in a protected wild mountain area could provide useful information on its composition in such environmental conditions, their role as environmental indicators and their forensic implications. For this reason, the Formicidae sarcosaprophagous community was studied at three different altitudes, between 400 and 1,500 m, in a wild mountainous area in the southeast of Spain using a modified Schoenly trap, with two pitfall traps inside, baited with 5 kg piglets (Sus scrofa L.). This work illustrates an approach to the community of the Formicidae, as a representative of the sarcosaprophagous community in an altitudinal gradient, showing a great variability in its composition. Furthermore, when comparing our results with other studies carried out in the Iberian Peninsula, we are able to suggest certain species with a potential utility as geographic and environmental indicators. Thus, Iberoformica subrufa, Lasius brunneus, Lasius cinereus and Camponotus sylvaticus are species of special interest as they appeared in either one of the sampled areas or in the same region.  相似文献   

20.
Chromosome numbers in 80 populations belonging to 18 species of Potentilla L. subgen. Potentilla from the Iberian Peninsula and two of P. maura, a North African endemic taxon, have been counted. The basic number of chromosomes is always x = 7 and these chromosomes are small (between 1 and 2 μm). For three species, the number of chromosomes is reported for the first time and, for another six, this number has been established in Iberian representatives. Moreover, new ploidy levels have been obtained for P. hispanica and P. crantzii with regard to their entire distribution area, and in P. cinerea and P. neumanniana for the Iberian Peninsula. Some taxonomic, phylogenetic and phytogeographic comments are made for several species or groups of species from the West Mediterranean region. In 13 species only one ploidy level has been found, but six species have several ploidy levels. Seven ploidy levels occur in the investigated taxa. The frequency of each ploidy level represented within Iberian Potentilla is analysed and the data are compared with those available for taxa from the rest of the distribution area of the genus.  相似文献   

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