Ephemeropteran Species Research Articles

Inventory and pattern of distribution of mayflies (Insecta, Ephemeroptera) in the Draa river basin, southern Morocco

The Draa river basin is located south of the High Atlas Mountain rangee in Morocco. The Ephemeroptera (mayflies) fauna of its three sub-basins: the High, Middle, and Lower Draa are poorly known. This study contributes to the knowledge of Ephemeroptera and its distribution in relation to environmental parameters in this area. The larvae of Ephemeropteran species were collected during six field campaigns in 17 sites using a Surber sampler. A total of thirteen species belonging to ten genera and five families were identified. among which seven taxa were recorded for the first time in the southern Atlas area: Baetis maurus, Baetis rhodani, Cheleocloeon dimorphicum, Cloeon simile, Procloeon stagnicola, Labiobaetis neglectus and Oligoneuriopsis skhounate. The limits of distribution of most species can be explained by the increase in water temperature and electrical conductivity especially at lower altitudes.

The mitochondrial genomes of palaeopteran insects and insights into the early insect relationships

Phylogenetic relationships of basal insects remain a matter of discussion. In particular, the relationships among Ephemeroptera, Odonata and Neoptera are the focus of debate. In this study, we used a next-generation sequencing approach to reconstruct new mitochondrial genomes (mitogenomes) from 18 species of basal insects, including six representatives of Ephemeroptera and 11 of Odonata, plus one species belonging to Zygentoma. We then compared the structures of the newly sequenced mitogenomes. A tRNA gene cluster of IMQM was found in three ephemeropteran species, which may serve as a potential synapomorphy for the family Heptageniidae. Combined with published insect mitogenome sequences, we constructed a data matrix with all 37 mitochondrial genes of 85 taxa, which had a sampling concentrating on the palaeopteran lineages. Phylogenetic analyses were performed based on various data coding schemes, using maximum likelihood and Bayesian inferences under different models of sequence evolution. Our results generally recovered Zygentoma as a monophyletic group, which formed a sister group to Pterygota. This confirmed the relatively primitive position of Zygentoma to Ephemeroptera, Odonata and Neoptera. Analyses using site-heterogeneous CAT-GTR model strongly supported the Palaeoptera clade, with the monophyletic Ephemeroptera being sister to the monophyletic Odonata. In addition, a sister group relationship between Palaeoptera and Neoptera was supported by the current mitogenomic data.

Ephemeroptera communities as bioindicators of the suitability of headwater streams for restocking with white-clawed crayfish, Austropotamobius pallipes

Currently, the distribution of the European native white-clawed crayfish (Austropotamobius pallipes) is restricted and fragmented over its range. Many European countries have active programmes for conservation of the species, including reintroduction programmes. Here, we have studied four brooks that were restocked with crayfish coming from population rescue from the Brissionnières after a drought in summer 2009. The aim was to validate the use of Ephemeropteran communities as potential bioindicators to select brooks for crayfish restocking. Restocked brooks were surveyed in 2010 and 2012. All brooks showed chemical and physical parameters in accordance with A. pallipes requirements. Three brooks which had high Ephemeropteran richness including Leptophlebiidae species (Habrophlebia lauta and Paraleptophlebia submarginata) have been restocked successfully. No crayfish were observed during the survey in Le Peu, which had only two Ephemeropteran species tolerant of reduced water quality and had no Leptophlebiidae species. Ecological characteristics of Ephemeropteran species and the limitations of their use as bioindicators to select brook for restocking are discussed.

Risk assessment using the species sensitivity distribution method: Data quality versus data quantity

Species sensitivity distributions (SSDs) are cumulative distributions of measures of species sensitivity to a stressor or toxicant, and are used to estimate concentrations that will protect p% of a community (PCp ). There is conflict between the desire to use high-quality sensitivity data in SSDs, and to construct them with a large number of species forming a representative sample. Trade-offs between data quality and quantity were investigated using the effects of increasing salinity on the macroinvertebrate community from the Hunter River catchment, in eastern Australia. Five SSDs were constructed, representing five points along a continuum of data quality versus data quantity and representativeness. This continuum was achieved by the various inclusion/exclusion of censored data, nonmodeled data, and extrapolation from related species. Protective concentrations were estimated using the Burr type III distribution, Kaplan-Meier survival function, and two Bayesian statistical models. The dominant taxonomic group was the prime determinant of protective concentrations, with an increase in PC95 values resulting from a decrease in the proportion of Ephemeropteran species included in the SSD. In addition, decreases in data quantity in a SSD decreased community representativeness. The authors suggest, at least for salinity, that the inclusion of right censored data provides a more representative sample of species that reflects the natural biotic assemblage of an area to be protected, and will therefore improve risk assessment.

LIFE HISTORY DOES MATTER IN ASSESSING POTENTIAL ECOLOGICAL IMPACTS OF THERMAL CHANGES ON AQUATIC MACROINVERTEBRATES

ABSTRACTThermal alteration is associated with ecological change in freshwater systems. Global climate change is likely to amplify thermal stresses on aquatic systems. We used cumulative daily heat units to examine potential impacts of temperature changes on selected aquatic organisms using scenario analyses. We selected two species of aquatic macroinvertebrates to test our hypotheses of thermal effects on life history pattern, viz. a univoltine stenothermic ephemeropteran species of conservation importance, and a multivoltine dipteran pest species. A combination of spreadsheet probability and logistic regression models was used to model probabilities of hatching and breeding success, plus population sizes and generation numbers per month, under current and projected 2 °C warmer water temperature scenarios. We propose that cold‐adapted Gondwanaland relic species are likely to become increasingly vulnerable and range limited, whereas multivoltine pest species are likely to become more abundant under scenarios of increased water temperatures. We propose management options that include maintaining river connectivity and dam re‐operation as potential mitigation measures. Copyright © 2012 John Wiley & Sons, Ltd.

Longitudinal extent of acidification effects of plantation forest on benthic macroinvertebrate communities in soft water streams: evidence for localised impact and temporal ecological recovery

Plantation conifer forest can increase the risk of acidification in acid-sensitive catchments with consequences for macroinvertebrates and ecosystem functioning. This study compared headwater streams in forested and non-forested catchments to appraise the distance required for the acid effect on macroinvertebrates to diminish downstream. Strict criteria were followed in the selection of paired streams, including similarities in elevation, aspect, stream order, geographical proximity, geology and soil type, with no inflowing tributaries in the first 2.5 km and no major land-use other than plantation forest and moorland. Consequently two headwater streams (one forested, one non-forested) drained Ordovician sedimentary geology and two headwater streams (one forested, one non-forested) drained Old Red Sandstone (ORS) were selected. All streams drained peaty soils. Up to six sites at 500 m intervals were sampled in triplicate by multihabitat kick sampling. Ecological impact and recovery from acid effects involved the entire macroinvertebrate community, but varied between seasons. Acid-sensitive Ephemeroptera revealed marked effects of episodic acidification, with Baetis rhodani and Rhithrogena semicolorata found to be transient between seasons. The increase in acid-sensitive ephemeropteran species with increasing distance downstream indicates the finite effects of forest mediated acidification on soft water streams in Ireland. Ecological impact appears, therefore, to be localised within the catchment, with ecological recovery occurring a short distance downstream. This is the first study to have reported such results.

충주 국망산 일대 수계의 저서성 대형무척추동물 군집

An ecological survey was conducted to examine the characteristics of benthic macroinvertebrate community inhabiting adjacent streams originated from Mt. Gukmang in July 2007. The benthic macroinvertebrate taxa represented total 60 species belonging to 15 orders, 6 classes and 4 phyla from the qualitative and quantitative sampling. Among these, a total of 47 aquatic insect species (78.3%) were comprised of the major groups in all communities. The relative abundance of Ephemeroptera, Diptera, Platyhelminthes and Trichoptera was 55.5%, 15.4%, 9.4%, and 8.8%, respectively. According to results, ephemeropteran species were major dominant taxa. The primary dominant species was Baetis fuscatus (19.0%) followed by Ecdyonurus kibunensis (16.5%), Dugesia sp. (9.4%), Chironomidae sp.1 (5.9%), and Baetis silvaticus (5.0%). The average values of dominant index (DI), diversity index (H

Ephemeropteran community structure and spatial stability of local populations of the major species group in the Keumho River

AbstractThis study was conducted to analyze the community structure of mayflies and stabilizing points for the local populations in relation to longitudinal changes in the Keumho River, Korea. A total of 22 ephemeropteran species occurred in the main riverine system during the sampling period of 3 years. The results indicated that Baetis fuscatus (mean density of 117.3 individuals/m2), Ecdyonurus levis (54.1), Uracanthella rufa (51.3) and Caenis KUa (49.9) comprised the major species group of the ephemeropteran community. The results of statistical analyses showed that these four species were distinguished from the others in terms of their mean densities. Longitudinal patterns based on total species numbers and numbers of individuals were characterized into three phases. A new approach was applied to analyze stabilized points for local populations based on the River Continuum Concept and density‐dependent mechanisms among local populations in a metapopulation. Stabilized local populations of B. fuscatus and E. levis occurred coincidentally at two points that were approximately 45 and 75 km away from the Youngchun Dam. Caenis KUa was locally stabilized at two points that were 40 and 60 km away from the dam. Uracanthella rufa showed only one stabilized local population at a point approximately 80 km away from the dam. The diversity index for the ephemeropteran community was compared with that calculated for the benthic macroinvertebrate community, and their similarity is discussed.

Ephemeroptera egg chorion characters: a test of their importance in assessing phylogenetic relationships.

The egg chorion ultrastructures of the Hermanella-Traverella (Insecta: Ephemeroptera) species complex were studied from a comparative point of view and used for the first time in a cladistic analysis. Egg characters, along with other nymphal and adult morphological characters, were used to assess the phylogenetic relationships of the species complex. In order to test the value of egg characters, analyses were performed on three matrices: 1) egg characters alone, 2) adult and nymphal characters, and 3) adult, nymphal, and egg characters. The computer program Pee-Wee was used to carry out the analysis. The cladistic analysis confirmed the value and potential of egg chorionic characters in assessing the phylogenetic relationships among ephemeropteran species. Egg characters, when added to the nymphal and adult character matrix, provided extra support to the monophyletic nature of the Hermanella-Traverella complex. Previously weakly defined clades were also resolved based on the new evidence. In the species studied the egg chorionic structures as well as their shape did not change after oviposition or water immersion, remaining constant through the different maturation stages of each species (mature nymph, subimago, and imago). For this reason, the eggs are a valuable source of information to unambiguously identify and associate a nymph to its correspondent adult stage when rearing is not possible.

Insects of a small aestival stream in northern Sweden

The insects of a small and cold aestival stream in northern Sweden were studied from semiquantitative kick-samples taken every ten days throughout the ice-free season in 1987. The stream froze solid at least in some sections in some winters. In addition to dipterans that were only identified to the family level, five ephemeropteran, four plecopteran, 11 coleopteran (Dytiscidae), and four trichopteran (Limnephilidae) species were found. Baetis bundyae Lemkuhl, Heptagenia orbiticola Kluge (Ephemeroptera), Nemoura cinerea (Retzius) (Plecoptera), Hydroporus palustris (L), Agabus setulosus (J. Sahlberg) (Coleoptera), Anabolia concentrica (Zetterstedt), Limnephilus coenosus Curtis, and Micopterna sequax McLachlan (Trichoptera) were all common. Malaise trap data are given for Plecoptera. The two ephemeropteran species Heptagenia orbiticola and Metretopus alter Bengtsson, and the plecopteran species Nemoura viki Lillehammer were recorded for the first time in Sweden. The remarkable species composition was attributed to the harsh abiotic and poorly studied environment. We predicted that the larval composition of this stream was representative for aestival streams in northernmost Fennoscandia.

Forests and the temperature of upland streams in Wales: a modelling exploration of the biological effects

SUMMARY. 1. Daily temperature data from six streams in upland Wales were used to explore the thermal effects of afforestation on stream ecology. The data were linked to published biological models to simulate fish and invertebrate development.2. Mean daily temperatures in forest streams were lower than those of moorland streams in spring and summer, and higher in winter. These spatial comparisons were supported by the results of experimental bank‐side clearance at a forest site, where there was evidence that stream temperatures fell in winter and rose in spring following treatment.3. Simulations indicated that brown trout (Salmo trutta) could weigh over 30% more by the end of their second growing season in a moorland compared with a forest stream. Several species of insects showed slower simulated egg development at forest sites. For two ephemeropteran species simulated nymphal growth was also retarded, suggesting significant alterations to the life cycle. Two plecopteran species were affected only slightly by the different temperature regimes.4. Overall, the simulations suggested that afforestation, by reducing summer temperatures, could lead to marked reductions in rates of development of some invertebrates and fish.

Estimates of annual production for some aquatic insects from the La Trobe River, Victoria

Annual production was estimated by the size-frequency method for Ephemeroptera (Tasmanocoenis tonnoiri, two species of Baetis, Atalonella spp., Atulophlebioides sp.), Plecoptera (Leptoperla spp.) and Trichoptera (Ecnomus sp.) at four sites on the lowland section of the La Trobe River. Annual production (P) of individual ephemeropteran species (or genera) varied from 0.02 to 0.7 g m-2 while total annual production of this order at two sites was 0.7-1 . 5 g m-. Annual production of Leptoperla spp. was 0.03 g m-2 at one site while Ecnomus sp, averaged 2 g m-2 at two sites. Estimates of annual production were subject to an error of at least t 50%. Annual turnover ratios (P/B; B is mean biomass) varied from 9 to 19 and were three to four times higher than published values for similar-sized macroinvertebrates in the temperate zone (generally < 15°C mean annual habitat temperature). This probably resulted from the higher average temperatures (17-18°C) at most sites.