RESUMO
Community assembly is determined by a combination of historical events and contemporary processes that are difficult to disentangle, but eco-evolutionary mechanisms may be uncovered by the joint analysis of species and genetic diversity across multiple sites. Mountain streams across Europe harbour highly diverse macroinvertebrate communities whose composition and turnover (replacement of taxa) among sites and regions remain poorly known. We studied whole-community biodiversity within and among six mountain regions along a latitudinal transect from Morocco to Scandinavia at three levels of taxonomic hierarchy: genus, species and haplotypes. Using DNA barcoding of four insect families (>3100 individuals, 118 species) across 62 streams, we found that measures of local and regional diversity and intraregional turnover generally declined slightly towards northern latitudes. However, at all hierarchical levels we found complete (haplotype) or high (species, genus) turnover among regions (and even among sites within regions), which counters the expectations of Pleistocene postglacial northward expansion from southern refugia. Species distributions were mostly correlated with environmental conditions, suggesting a strong role of lineage- or species-specific traits in determining local and latitudinal community composition, lineage diversification and phylogenetic community structure (e.g., loss of Coleoptera, but not Ephemeroptera, at northern sites). High intraspecific genetic structure within regions, even in northernmost sites, reflects species-specific dispersal and demographic histories and indicates postglacial migration from geographically scattered refugia, rather than from only southern areas. Overall, patterns were not strongly concordant across hierarchical levels, but consistent with the overriding influence of environmental factors determining community composition at the species and genus levels.
Assuntos
Biodiversidade , Clima , Insetos/classificação , Rios , Animais , Europa (Continente) , Geografia , Haplótipos , Filogenia , Especificidade da EspécieRESUMO
In total 24 species of aquatic Empididae (Clinocerinae and Hemerodromiinae) are known from the Sierra Nevada Mountains of Spain, including five new species (Hemerodromia planti Ivkovic & Sinclair sp. nov., Kowarzia nevadensis Sinclair & Ivkovic sp. nov., Wiedemannia darioi Sinclair & Ivkovic sp. nov., W. horvati Ivkovic & Sinclair sp. nov. and W. vedranae Ivkovic & Sinclair sp. nov.). The new species are described, illustrated and distribution of all species listed. Wiedemannia (Philolutra) angelieri Vaillant and W. (Roederella) ouedorum Vaillant are newly recorded in Sierra Nevada and nine species are endemic to this region. A key to all 24 species of aquatic empidids is presented.
Assuntos
Organismos Aquáticos/classificação , Dípteros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Dípteros/anatomia & histologia , Ecossistema , Feminino , Masculino , Nevada , EspanhaRESUMO
Sierra Nevada (southern Iberian Peninsula) harbours a great biodiversity and the studies on some aquatic insect groups have been and continue to be numerous there. This database brings together information on Plecoptera, Trichoptera and Coleoptera inhabiting running waters of this mountain system above 800 m of altitude. It includes data on the number, life stage and sex of individuals as well as the available information on abiotic characteristics of their habitats. The dataset is composed of 1,718 sampling events carried out between 1901 and 2022 in approximately 60 different water bodies, 15,347 occurrences pertaining to more than 203,000 individuals, and 10,173 records of associated measurements (23 physico-chemical parameters). The dataset is the result of a comprehensive review of scientific literature and of integrating data from recent research projects and the Sierra Nevada Global-Change Observatory's long-term monitoring data. This information is valuable for those studying past distributions and abundances of the species in the dataset, for building predictive models or just studying temporal trends in the current context of climate change.
Assuntos
Besouros , Ecossistema , Animais , Espanha , Insetos , Biodiversidade , Mudança ClimáticaRESUMO
Several studies on global change over the next century predict increases in mean air temperatures of between 1°C to 5°C that would affect not only water temperature but also river flow. Climate is the predominant environmental driver of thermal and flow regimes of freshwater ecosystems, determining survival, growth, metabolism, phenology and behaviour as well as biotic interactions of aquatic fauna. Thus, these changes would also have consequences for species phenology, their distribution range, and the composition and dynamics of communities. These effects are expected to be especially severe in the Mediterranean basin due its particular climate conditions, seriously threatening Southern European ecosystems. In addition, species with restricted distributions and narrow ecological requirements, such as those living in the headwaters of rivers, will be severely affected. The study area corresponds to the Spanish Mediterranean and Balearic Islands, delimited by the Köppen climate boundary. With the application of the MEDPACS (MEDiterranean Prediction And Classification System) predictive approach, the macroinvertebrate community was predicted for current conditions and compared with three posible scenarios of watertemperature increase and its associated water flow reductions. The results indicate that the aquatic macroinvertebrate communities will undergo a drastic impact, with reductions in taxa richness for each scenario in relation to simulated current conditions, accompanied by changes in the taxa distribution pattern. Accordingly, the distribution area of most of the taxa (65.96%) inhabiting the mid-high elevations would contract and rise in altitude. Thus, families containing a great number of generalist species will move upstream to colonize new zones with lower water temperatures. By contrast, more vulnerable taxa will undergo reductions in their distribution area.
Assuntos
Mudança Climática , Ecossistema , Invertebrados/fisiologia , Rios , Altitude , Análise de Variância , Animais , Geografia , Mar Mediterrâneo , Modelos Teóricos , EspanhaRESUMO
Descriptions of the previously unknown larvae of Annitella esparraguera and A. iglesiasi, two European endemic species from the southern Iberian Peninsula are presented. The most important diagnostic features are illustrated and some taxonomic, zoogeographical and ecological notes are given. In addition, a previous key is modified to include these two new Iberian Limnephilidae larvae.