Ephemeroptera Research Articles

PRELIMINARY RESULTS ON SPECIES COMPOSITION OF AQUATIC INSECTS IN DAI DINH TOWN, TAM DAO DISTRICT, VINH PHUC PROVINCE

In this study, specimens were collected at 5 different sites. The aquatic insects were collected both quantitatively by Surber net (size 50 cm × 50 cm, mesh size 0.2 mm) and qualitatively by hand net and pond net. A field survey was conducted in December 2019 (dry season) and in June 2020 (rainy season). The study aims to show the preliminary data on faunas and communities of aquatic insects in Dai Dinh town, Tam Dao district, Vinh Phuc province. As a result, a total of 91 aquatic insect species belonging to 76 genera, 44 families, and 9 orders were recognized. Among these, the order Ephemeroptera had the highest species number with 32 species; followed by order Trichoptera with 18 species; order Odonata with 16 species; order Coleoptera with 8 species; order Hemiptera and Diptera with 6 species, each; order Plecoptera with 3 species. Order Lepidoptera and Megaloptera had the lowest of species number, represented by 1 species for each order. Besides, the quantitative analysis results and the functional feeding groups were provided in this study.

Effects of Local Environmental and Landscape Variables on the Taxonomic and Trophic Composition of Aquatic Insects in a Rare Forest Formation of the Brazilian Amazon.

In the present study, we analyzed a unique phytophysiognomy in the Amazon region, which is formed by savanna-like vegetation on iron-rich soil (known locally as canga) located within an iron-ore mining region. We used the habitat template theory to test the hypothesis that changes in the physical-chemical properties of streams and the physical structure of their habitats at in-stream and micro-basin (landscape) levels affect the taxonomic and trophic composition of immature aquatic insects. For this, we used a local environmental matrix composed of nine physical-chemical and structural habitat variables, together with the Habitat Integrity Index. We also calculated landscape metrics based on the area of the micro-basin, such as relief, slope, mean current flow, and vegetation cover. We divided the aquatic insects into five functional feeding groups based on their diet and food sources. Our results indicate that changes in the trophic level of the insects of the orders Ephemeroptera, Plecoptera, and Trichoptera are more easily observed than the taxonomic structure of communities. The loss of environmental integrity and vegetation cover were responsible for 84% of the variation observed in the composition of functional feeding groups (FFGs). Our study shows that aquatic insect communities in the canga and in the Amazon regions dominated by forest require specific in-stream and landscape conditions. These findings reinforce the need for the preservation of areas of canga vegetation, which not only have a unique levels of biological diversity, but are also targeted for the exploitation of their economically valuable natural resources.

Bioaccumulation of heavy metals in an aquatic insect (Baetis pavidus; Baetidae; Ephemeroptera) in the El Harrach Wadi (Algeria)

Baetis pavidus is considered the larva of aquatic insects belonging to the order Ephemeroptera. These ephemeral larvae measure 1 cm on average, and adults have a very short imaginal life. These ephemerals are a widely used biomonitoring tool; they are good indicators of water quality. In this study, we investigated the spatial variability in the bioaccumulation of four metallic trace elements (Hg, Pb, Cu, and Zn) in Baetis pavidus as a function of environmental parameters in the El Harrach Wadi, which crosses Algiers, the capital of Algeria. The sampling was carried out monthly over 13 months, from May 2011 to May 2012; ten (10) stations were selected along the Wadi, distributed between altitudes of 11 and 220 m. A variance analysis (ANOVA I) was carried out to study the spatial variability in the bioaccumulation of the trace elements in Baetis pavidus to determine whether heavy metal levels were significantly different between study stations. Significant correlations were recorded between concentrations of heavy metals in the water and water physicochemical parameters. In this study, the bioaccumulation of Hg and Pb varied significantly from upstream to downstream, but there was no significant difference in the bioaccumulation of Cu and Zn. Redundancy analysis (RDA) showed that the bioaccumulation of copper, zinc, and lead depended on the temperature of the water, calcium, and nitrates. The concentrations of mercury, lead, copper, and zinc accumulated in Baetis pavidus based on the environmental parameters, confirming strong contamination of the El Harrach Wadi water system by these four metallic trace elements.

Phylogeny and classification of Leptophlebiidae (Ephemeroptera) with an emphasis on Neotropical fauna

AbstractMayflies from the family Leptophlebiidae are cosmopolitan and highly diverse morphologically; they are also the largest family in numbers of genera and the second in number of species in the order Ephemeroptera. In spite of their broad diversity and the efforts employed to understand the evolution of this group, the internal classification of Leptophlebiidae remains controversial at all levels. More recently, important changes have been incorporated into the systematics of the family, increasing the number of subfamilies (from two to six) and recognizing several tribes. We present a phylogeny of the family based on 153 taxa (53 genera) and two molecular markers, representing 1655 bp, and verify the taxonomic status of the subfamilies, tribes and complexes. Based on these results, the number of subfamilies has been increased from six to eight and one new tribes and two new subtribes have been added. In addition, new ranks are proposed and the concept of Atalophlebiinae revised, including genera with distributions in the Australasian and Neotropical regions.

Diversity of EPT (Ephemeroptera, Plecoptera, Trichoptera) Along Streams Fragmented by Waterfalls in the Brazilian Savanna.

In stream ecosystems, waterfalls intercept the fluvial continuum and limit the dispersion of aquatic organisms. However, the barrier effect may be minimized or absent for insects whose life cycle is not restricted to the aquatic environment (i.e., winged adults), such as the orders Ephemeroptera, Plecoptera and Trichoptera (EPT). In this study, we investigated EPT diversity (abundance, richness, and composition) in savanna headwater streams (Cerrado Domain, Brazil) to investigate the hypothesis that large waterfalls have little effect on instream assemblage structure. During 2017 and 2018, we sampled EPTs and measured environmental conditions at reaches adjacent (downstream and upstream) to waterfalls (5 to 70m high). We collected 2532 immature specimens of 33 genera, including the first record of 14 genera of Ephemeroptera, 11 Trichoptera, and three Plecoptera for the Tocantins State. Hydro-geomorphic and streambed conditions varied among sites, but they were not related to the presence of waterfalls. Assemblage structure was similar between downstream and upstream reaches, with no significant difference in taxa richness, abundance, and composition. This pattern was consistently observed considering all data combined, and each order separately. These results support the hypothesis that physical barriers have weak effects on EPT assemblages at small spatial scales, where strong dispersal and habitat similarity probably homogenizes the structure of local assemblages in stream corridors adjacent to large waterfalls. The study provides important information about factors driving the distribution of biodiversity in savanna streams, which are relevant to support conservation and management plans in the Brazilian Cerrado.

Campsurus truncatus Ulmer, 1920 (Polymitarcyidae): an Ephemeroptera in eutrophic waters

Abstract: Aim The order Ephemeroptera, together with Trichoptera and Plecoptera, has been considered as sensitive in environmental quality assessment. However, the species Campsurus truncatus Ulmer 1920 (Polymitarcyidae) has been sampled in anthropically altered sites. In this paper, data on the occurrence of that species in the water quality monitoring network of the Environmental Agency of São Paulo State (CETESB) were gathered to review its position in the environmental gradient and in the quality assessment of rivers and reservoirs. Methods For this, a compilation of the occurrences and densities of Campsurus obtained in rivers and reservoirs of São Paulo state between 2001 and 2018, with grab samplers, was carried. Environmental factors, the Trophic State Index (TSI) and the Benthic Community Index (BCI) were related to the species densities to define its environmental requirements. Results The sublittoral zone of reservoirs was the most common habitat to C. truncatus, occurring more frequently at mesotrophic sites with fair ecological quality. Higher mean densities were recorded at eutrophic sites with good ecological quality conditions. The statistical analysis did not show linear correlation between C. truncatus densities and any of the analyzed environmental variable such as grain size, organic matter content, DO and light penetration, although there was a tendency for higher species densities occur in muddy, dark sediments and with intermediate levels of organic matter. As described in literature the presence of aquatic plants can actually benefit that population once the highest densities were observed in sites with many macrophytes, as Salto Grande reservoir, but it may be confusing the relationship between population density and environmental factors. Conclusions The high occurrence and densities of C. truncatus obtained in eutrophic environments suggest that the species should not be considered as a sensitive taxon in qualitative indexes, such as the BCI for rivers and the sublittoral region of reservoirs. Moreover, its exclusion from the richness of sensitive groups had low impact on the diagnoses already performed at the CETESB monitoring network.

The role of spatial and environmental variables in shaping aquatic insect assemblages in two protected areas in the transition area between Cerrado and Amazônia

Abstract: The distribution of aquatic insects of the orders Ephemeroptera, Plecoptera, and Trichoptera (EPT) can be influenced by factors such as water quality, habitat integrity and biogeography. The present study evaluated the structure of EPT assemblages in streams in the Cerrado, a global biodiversity hotspot. Samples were collected from 20 streams in two protected areas: Parque Estadual do Mirador (10 streams) and Parque Nacional da Chapada das Mesas (10 streams). A total of 1987 specimens were collected, representing 46 taxa of EPT. The two study areas did not differ significantly in taxonomic richness of EPT genera (t = -1.119, p = 0.279) and abundance of individuals (t = 0.268, p = 0.791) but did differ in genus composition (Pseudo-F = 2.088, R2 = 0.103, p = 0.015) and environmental variables (Pseudo-F = 2,282, R2 = 0.112, p = 0.014). None of the tested environmental variables were correlated with the community but a spatial filter captured an effect of the spatial distribution of streams. The region of the study is located in MATOPIBA, which is the last agricultural frontier of the Cerrado. Therefore, it is important that there is police and monitoring so that the “Parque Estadual do Mirador” and the “Parque Nacional da Chapada das Mesas” continue to play their role in conserving biodiversity in the future.

Taxonomy of benthic macroinvertebrates in Jajrud River for water quality assessment

The invertebrates are one of the most important terrestrial fauna and freshwater taxa.Benthic macroinvertebrates include aquatic insects and spiders, mites, crustaceans, andspecies of mollusks and worms that are aquatic in their immature stages and terrestrial intheir adult stage. Jajrud River originates from the Alborz Mountains and is a source ofdrinking water for people in eastern part of Tehran and the surrounding villages. For thetaxonomic identification of benthic macroinvertebrates, five stations downstream of Jajrudwere used. A Surber sampler device was used for sampling with dimensions 30 × 30 cmand mesh size of 250 microns in all four seasons of the year 2013 with three repetitions ateach station. In total, five orders (Ephemeroptera, Coleoptera, Diptera, Trichoptera, andOligochaeta) and 13 families of benthic macroinvertebrates were identified. In all stations,the family Baetidae (Baetis sp .) belonging to the order Ephemeroptera had the highestabundance, and seasonally the highest abundance was detected in autumn, winter, summer,and spring respectively. After the identification of benthic macroinvertebrates, five bioticindices including EPT, HFBI, SIGNAL, NJIS, and MMIF were calculated for water qualityassessment in downstream of the Jajrud River. Regarding the results of the biotic indices, itcan be said that the water quality of downstream of Jajrud River is not favorable. Therefore,appropriate management measures should be taken to improve river water quality.

Water quality assessment of Rawanduz River and Gali Ali Beg stream by applied CCME WQI with survey aquatic insects (Ephemeroptera)

The population of Ephemeroptera was studied in three selected stations of Rawanduz River (Gali Ali Beg water fall, Rawanduz River and after the junction of these two waters) during the three seasons of spring, summer and autumn in 2016. In addition,sixteen physicochemical parameters (pH, EC, turbidity, DO, BOD5, NO3, TDN, TDP, HCO3-, Hardness, Ca2+, Mg2+, Na+, K+, Cl-, SO42-, Na% and SAR) of water in these stations were estimated and used to calculate the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI). Eleven species of aquatic insects were identified,which belong to four families of the order Ephemeroptera. Three of the studied species are described for the first time. According to water quality index, the water was ranked as poor for drinking and marginal for irrigation purposes.

Evaluation of the Effectiveness of a “Hand-Pairing” Cross-Breeding Experiment in Ephemeroptera

The insect order Ephemeroptera is the basal lineage of wing acquired insects (i.e. Pterygota), and is a key taxon in understanding the processes of insect diversification and phylogeny. Therefore, phylogenetic evolution and evolutionary developmental studies of this insect order have been desirable, but such studies have been delayed due to various barriers. One of the greatest factors is the difficulty of creating suitable captive breeding conditions and the difficulty of controlling mating and embryogenesis. Under such circumstances, however, we recently established a method to control fertilization and developmental initiation using a “hand-pairing” cross-breeding method. This method was established using Dipteromimus tipuliformis of the family Dipteromimidae, which is endemic to the Japanese Islands. In addition, in this study, it was revealed that the “hand-pairing” method was also effective in Ephemeridae and Baetidae, which are largely differentiated phylogenetically from the family Dipteromimidae. As such, it is considered that our established “hand-pairing” cross-breeding method is widely effective among mayflies. This is considered to be an important outcome that will contribute to future evolutionary developmental experiments on mayflies.

Active reintroduction of benthic invertebrates to increase stream biodiversity

A large number of restoration projects aims to improve the ecological quality of streams and rivers by focusing on the stream structure. However, improved habitat heterogeneity often does not lead to natural recolonization by sensitive freshwater macroinvertebrate communities, particularly when the recolonization potential is low and source populations are absent. In preliminary studies we tested whether natural substrate exposures could be used to sample and transport benthic macroinvertebrates. In this pilot study we used these previously tested natural substrate exposures to sample freshwater invertebrates in a donor stream in order to actively (re-)colonize a recipient stream. In the course of three reintroduction campaigns, we were able to accumulate over 350,000 benthic invertebrates, including 25 indicator taxa of the orders Ephemeroptera, Plecoptera and Trichoptera and 30 taxa scoring positive in the German Fauna Index. In total, 45 taxa, which did not occur in the recipient stream before, were reintroduced. They were transported gently within natural substrate exposures and released on a stream bottom area of 500 m2 in the recipient stream. We intended to study if an increase of benthos fauna in a recipient stream is possible, and if this increase will eventually improve the ecological status. So far, the natural substrate exposure-method demonstrated to be an adequate tool to accumulate and transport benthic macroinvertebrates and, in general, has the potential to increase the biodiversity of streams when used as assisted migration measure.

COMPOSICIÓN Y TAXONOMIA DE LA FAMILIA BAETIDAE (INSECTA: EPHEMEROPTERA) PARA LA CUENCA DEL RÍO LA VIEJA, ALTO CAUCA, COLOMBIA.

Baetidae es una de las familias de insectos más abundantes y diversas del orden Ephemeroptera. En Colombia se registran 38 especies en 19 géneros, de las cuales cinco especies se localizan en la cuenca del Río La Vieja: Andesiops peruvianus, Camelobaetidius edmunsi, Mayobaetis ellenae, Nanomis galera y Prebaetodes sitesi. En este trabajo, se examinaron un total de 7226 ninfas de baetidos, colectadas en el Río La Vieja, pertenecientes a 23 especies en 11 géneros. Se encontró que el género más abundante y con mayor riqueza es Baetodes seguido por Camelobaetidius (10 individuos y tres especies determinadas respectivamente), las especies más abundantes fueron Baetodes awa y Camelobaetidius edmunsi (con 3563 y 1282 individuos respectivamente). En el presente trabajo se registra por primera vez, para el Río La Vieja, dos géneros (Cloeodes y Varipes) y ocho especies (Baetodes awa, Baetodes diasae, Baetodes pseudospinae, Camelobaetidius mathuriae, Camelobaetidius patricki, Nanomis rasmusseni, Prebaetodes meridinensis y Zelusia principales). Lo anterior establece que el rio La Vieja registra alrededor del 61 % de las especies de baetidos reconocidas para Colombia (23 de las 38 especies).

Evaluating the responses of taxa in the orders Ephemeroptera, Plecoptera and Trichoptera (EPT) to sediment stress in the Tsitsa River and its tributaries, Eastern Cape, South Africa.

Excessive delivery of fine sediment has been implicated as the main water quality stressor in the Tsitsa River catchment. This study evaluates the responses of the taxa Ephemeroptera, Plecoptera and Trichoptera (EPT) to suspended sediment and grain size distribution in eight selected study sites in the Tsitsa River catchment. The sampling of macroinvertebrates took place seasonally from August 2016 to April 2017 and EPT identified to either genus or species level. To avoid site redundancy, the sites were clustered into four groups, with groups 1 and 2 being more impacted when compared to groups 3 and 4. The results of the sediment grain size analysis revealed that sediment grain size distribution ranged from 0.121 to 5.61 μm; percent clay and percent silt were the most dominant sediment fractions across all groups. Among the EPT metrics examined, Shannon index, Simpson's index, evenness, Ephemeroptera abundance, EPT abundance and Trichoptera abundance were sensitive, differentiating between sediment groups 3 and 4 (less impacted groups) from 1 and 2 (highly impacted groups). Site groups 3 and 4 supported more EPT species, in terms of the number of individuals and diversity. Species such as Caenis sp., Pseudocloeon glaucum, Oligoneuropsis lawrencei and Baetis sp. were considered sediment-tolerant, displaying strong positive association with influenced groups. Taxa such as Hydropsyche sp., Pseudocloeon sp., Cheumatopsyche sp. and Afronurus sp. were considered sediment-sensitive. Overall, the present study revealed that genera/species within the order EPT were differentially sensitive to fine sediment stress and grain sizes, proving to be useful bioindicators.

Population variation in Neonicotinoid tolerance in nymphs of the Stenonema species complex of mayflies

Population variation in Neonicotinoid tolerance in nymphs of the Stenonema species complex of mayflies

Macroinvertebrates of the Tributaries of Upper Baleh River, Sarawak

Studies on Baleh River with respect to aquatic fauna currently remains limited. Hence, this paper presents thespecies richness and composition of macroinvertebrates14 tributaries of Upper Baleh River in Kapit Division,Sarawak. A total of 1,154 individuals from 10 orders, 43 families and 66 genera of macroinvertebrates werecollected. The highest number of macroinvertebrate was taken from Naah River (201 individuals) and the leastfrom Ukit River (15 individuals). The order Ephemeroptera was the most abundant, with 45% of the totalindividuals caught, followed by Trichoptera (23%), Hemiptera (10%), and Coleoptera (9%). Three biologicalindices were used to measure the diversity of macroinvertebrate of which the values of the indices were low:Shannon diversity index (1.54–2.54), Shannon evenness index (0.33–0.89) and Margalef richness index (1.67–4.90). The composition of functional feeding groups varies between first and fourth order streams, which ispossibly an indication of ecological effects of siltation due to logging activities in the area.

Giant Burrowing Mayfly (suggested common name) Hexagenia limbata (Serville 1829) (Insecta: Ephemeroptera: Ephemeroidea: Ephemeridae)

The giant burrowing mayfly, Hexagenia limbata (Serville, 1829) (Figure 1) is one of the most widespread mayflies in North America and is well known for its importance in ecosystem health and water quality monitoring. The mayflies (order Ephemeroptera) are an ancient lineage of aquatic insects originating more than 300 million years ago (Merritt and Cummins 2008). Within this order, the burrowing mayflies of the family Ephemeridae are well-known for their importance in fly fishing and their massive synchronized mating flights.https://edis.ifas.ufl.edu/in1244
 Also published on the Featured Creatures website: http://entnemdept.ufl.edu/creatures/AQUATIC/mayfly.html

The First Establishment of "Hand-Pairing" Cross-Breeding Method for the Most Ancestral Wing Acquired Insect Group.

Insects are the most diverse organisms in the world and have been in existence since ca. 480 Ma; given this, they can provide profound insights into evolution. Among them, the order Ephemeroptera is one of the most basal clades of winged insects. This makes Ephemeroptera a significant key taxon in understanding the macro-evolution or the insect groundplan. In the development of biological evolutionary studies of this taxon, it is important to establish a technique for cross-breeding. Furthermore, the establishment of these techniques also makes a great contribution in the fields of micro-evolution. In a non-model taxon, the mayfly, subcultivation in the laboratory has been thus far considered impossible. With the exception of some parthenogenetic strains, it is extremely difficult to mate these insects in artificial environments. In this study, we established a successful artificial mating technique, i.e., a "hand-pairing" based cross-breeding method for mayflies. Furthermore, we also succeeded in clearly verifying by a genotyping method that the offspring reproduced by hand-pairing were in fact derived from the actual male and female which were used for hand-pairing. We established a reproductive experimental technique for hand-pairing of Dipteromimus tipuliformis and verified this technique by means genotyping. This technique could allow the artificial control of fertilization timing, and result in offspring which can be verified as to their status by means of genotyping. This achievement will be extremely important in the future for both the macro- and micro-evolutionary studies of insects.

Bioassessment of river ganga in Uttarakhand stretch (India) using benthic macro-invertebrates as bioindicator

The sedentary lives of macro-invertebrates enable them to act as continuous monitor of water quality of freshwater bodies. Some specific families of benthic macro-invertebrate fauna belonging particularly to the Order Ephemeroptera, Trichoptera, Plecoptera, Hemiptera, Coleoptera, Diptera, Molllusca, Crustacea, Odonata, Hirudinea, Oligochaeta, Polychaeta and Planaria have been recognized as bioindicator of water quality by Biological Monitoring Working Party (BMWP). The present study was carried out to explore the taxonomic richness of macro-zoobenthos found in various habitats and biological water quality of river Ganga in Uttarakhand stretch of India at 3 locations viz., Haridwar barrage, Jagjeetpur sewage treatment plant (STP) upstream and downstream. The samples were collected twice a year to elucidate seasonal variation in taxa occurrence. A total of 1, 560 individuals belonging to 32 families and 12 taxonomic orders were recorded. Biological water quality at Haridwar barrage was found to be clean in both the seasons. Direct discharge of untreated sewage from Jagjeetpur STP had profound effect on the biota of river and lead to community replacement at downstream of discharge. Dominant Ephemeroptera colonies were replaced by Diptera family Chironomidae at this location and thereby showed decline in biological water quality.

Morphology and evolution of the wing bullae in South American Leptophlebiidae (Ephemeroptera).

Insects were the first animals to take to the skies, and have been flying for over 320 million years. The order Ephemeroptera is, or at least is part of, the most early-diverging lineage of extant winged insects. The extant species present a very short adult life span, mainly dedicated to reproduction and dispersal of eggs. Mating and egg-laying behavior depend on flight. Wings are structures to fly and as such face a number of physical and physiological challenges. The convex curvature along the anterior-posterior axis of the wing generates a camber that must be carefully regulated. One of the most interesting ways of wing bending is provided by the bullae, which have been defined as short sections of flexible chitin, where the flexion lines cross veins. Although the bullae have been frequently used as taxonomic characters, there is no study focused on their morphology, although their prevalence on the wings of mayflies strongly suggests a role in flight. In order to identify evolutionary trends of these structures within Ephemeroptera, we constructed a matrix with comparative anatomy data of the bullae from whole mounts of the wings of 300 specimens belonging to 70 species of several mayfly families, as well as scanning microscopy samples of selected specimens. We also surveyed the number of bullae and their distribution in the wings of the different species within the South American Leptophlebiidae clade. We optimized the characters onto the latest published phylogeny for Leptophlebiidae.

Species composition diversity of aquatic insects in the Binh Hung Hoa biological pond system

This study surveyed and analyzed samples of aquatic insects at 10 pondst Binh Hung Hoa biological system on March and August in 2015. The results recorded 31 species belonging to 24 families, 6 orders, include Coleoptera, Diptera, Odonata, Hemiptera, Ephemeroptera and Trichoptera. In particular, the larvae of theory derdiptera had the best diversity of composition, wise distribution and high density. However, the larvae of t h e order ephemeroptera and order trichoptera had the least diversity and low level of density and distribution at maturation ponds. Among ponds, the diversity and density of aerobic pond and sedimentation pond were high while the maturation ponds were low. The composition of aquatic insects had high similarity in the same function ponds and low similarity in the different function ponds. The species composition diversity and abundance of aquatic insects were the highest in the sedimentation pond and lowest in the other ponds. In the rainy season, the species composition diversity of aquatic insects were higher than those in the dry season.