In May 2023 and 2024, the species composition and structure of chironomid communities in six lakes of the Altai Territory were studied. A total of 16 species of chironomids have been found in the lakes. It is shown that in shallow steppe drainless lakes, which are similar in morphology and soil composition and are characterized by a wide range of fluctuations in total mineralization throughout the year, the species composition of chironomids depends on the water salinity level during the subglacial period. In lakes with a salinity of up to 11% during the ice age, the species composition is much richer (7–10 species) compared with reservoirs with a winter salinity of over 11% (2–3 species). Larvae of two species Chironomus (Camptochironomus) gr. tentans and Chironomus (Chironomus) gr. thummi, which also occurred at higher salinity (24–38%) as subdominants in the community, achieved mass development in lakes with a winter salinity of 11–20%. At a salinity of 9–11%, Chironomus (Chironomus) gr. riparius was the absolute dominant. In the saltiest lake, Markovsky, larvae of Procladius (Holotanypus) sp predominated in number. In the least salty lake, the stemcommunity structure was more complex, with species of the sub-family Tanypodinae as dominants, three species of the sub-family Chironominae were classified as subdominants. The size and weight characteristics of larvae of different ages of mass species are given. The most promising lakes for chironomid fishing in the Altai Territory are reservoirs with a range of salinity in the subglacial period from 11 to 20%, where the largest larvae of the genus Chironomus dominate in number.

Based on the morphology of the polytene chromosomes, 21 species of the genus Chironomus Meigen from Bulgaria have been identified. Original pictures of the polytene chromosomes are presented for each species. "Basic" sequences were determined for each arm of the polytene chromosomes which are used to determine the corresponding arms of the chromosomes, and the cytocomplex to which the species belongs. The species are distributed in five cytocomplexes: thummi, pseudothummi, parathummi, lacunarius and modified thummi cytocomplexes. Marker sequences have been revealed on chromosome G that are proposed as a species identifier. Cytogenetic characters by which homosequential species of the genus Chironomus can be distinguished are discussed. This study emphasizes the importance of polytene chromosomes for the taxonomy of the species of Chironomus.

The larvae of the genus Chironomus are a common object for hydrobiological studies, as well as a model object for cytogenetics. Morphologically, the species are very similar. One of these species or species complex is Chironomus “annularius”, which has a Holarctic distribution. It has chromosomal banding sequences characteristic of Nearctic and Palearctic populations. Using an integrated method that included morphology, cytogenetics, and molecular genetics, we analyzed populations from Russia, Mongolia, and Armenia. We found through cytogenetics and larval morphology that the populations have high similarity. Molecular genetic studies have shown significant differences between the populations. The genetic distances between the populations, in some cases, exceed the interspecific threshold of 3%, and are 6.5%. In the South Caucasian population (Lake Sevan), a chromosomal banding sequence, h’annD3, that was previously observed only in North America, was found for the first time. The larvae from Lake Sevan have large genetic distances from others, and are morphologically similar to the species Chironomus markosjani Shilova 1983, described from this lake without comparison with Ch. annularius nor an exact description of the karyotype. The sequences of the COI genes from Montenegro (Lake Skadar) and West Siberia (Novosibirsk) found in GenBank may belong to a new undescribed species, or a species not represented in the database. Thus, the analyzed data on Chironomus “annularius” support the presence of the complex of homosequential species under this name.

The Indonesian government plans to turn Central Kalimantan into a national food barn by planting rice in several places, including in shallow peatlands. Tropical peatlands actually have limited potential for agricultural use because the growing medium in some cases is not conducive to root development, waterlogged soils that poison plants. The physical, chemical, and biological properties of water can be used as indicators to determine if a land is suitable for growing crops. The objective of this study is to analyze the physical, chemical, and biological properties of water in different aquatic ecosystems in peat swamp forest. This study was conducted in the Peat Techno Park (PTP) of the College of Palangka Raya, Central Kalimantan. Samples were collected from 9 observation stations with different forms of land use for agricultural activities, namely unplowed rice fields, plowed fields, swamps, connecting ditches, beje, natural peat swamp forests, ponds and irrigation ponds. Data collection was taken over a 6-month period and coincided with the peak of the dry season and the rainy season. Water properties were then analyzed by observing the parameters measured directly at the station, namely pH, temperature, dissolved oxygen (DO) and depth. The results showed that there were 4 (four) sites that had suitable water properties for agricultural uses, namely unplowed fields, plowed fields, swamps and ponds. There are only 2 (two) macrozoobenthos groups on PTP peat bogs, namely Annelida and insects. In addition, the most dominant group in insect belongs to the ordo Diptera, and family Chironomidae with the most common genus Chironomus. Conversion of peat swamp forest to rice fields and fish ponds promotes greater diversity and abundance of macroinvertebrate communities, with the depth significantly affecting them.

Chironomids can inhabit a large variety of water bodies. They contribute to the process of biological purification of water bodies, and they are a high-quality food for commercial fish. Any comprehensive study of biodiversity in water bodies begins with the investigation of chironomids, which are typically variable and difficult to identify through morphology. Similar species are called sibling-species. For precise identification, we used a comprehensive approach, including morphology, cytogenetics, and molecular genetics. In one sample from Kurchatskoe Lake (Tyumen reg.), with mineralized water of 7‰, we found three Chironomus species. Karyological analysis revealed seven banding sequences in Chironomus agilis2, eight in Ch. balatonicus, and seven in Camptochironomus tentans. The combination of balD1.2 was found in all Ch. balatonicus larvae. All the found banding sequences are typical for the studied region, and have previously been recorded in European and Altai populations. All the estimated genetic distances of COI gene sequences in the studied larvae of each species are much lower than the commonly accepted threshold of 3% in species of the genus Chironomus.



Study of stream insect fauna provide valuable insights into aspects of the stream channel ecosystem. The present study was conducted to investigate the aquatic stream living insect community, abundance and diversity in a hilly stream, Balukhali chora of Chittagong University campus to determine the water quality. The insects were collected with bottom dredge net from the edge and benthic regions of the Riffle zone and the Pool zone of the stream from January 2018 to December 2018. Insects were sampled using standard entomological method and determined their tolerance value. A total of 2535 insects were recorded, belonging to six insect orders, 30 families and 45 genera. The abundance ratio was higher in all the months in the Pool zone excepting the months of April, May, June and October. The orders Ephemeroptera, Odonata and Diptera were abundant in the Pool zone, while Hemiptera, Coleoptera and Lepidoptera were abundant in the Riffle zone. On the basis of Biotic Index, the most dominating orders Odonata and Hemiptera indicated good water quality, though the dipteran genus Chironomus spp. indicated poor quality in some of the months. The stream insect community structure of the two zones indicated that the overall water quality of the stream water was very good. Both manmade and natural interruption occurred in the stream channel due to human settlement, agricultural runoff and natural disasters. The study was conducted to know the abundance and diversity of aquatic insect community which indicated the water quality of the stream.

The karyotype features and gene COI sequence of Chironomusheteropilicornis Wülker, 1996 from the Gydan Peninsula are presented for the first time. Nine banding sequences were determined, eight of them hpiA2, hpiB1, hpiC1, hpiC2, hpiD1, hpiE1, hpiF3 and hpiG1 were previously known from European, Georgian (South Caucasus) and Siberian populations. One new banding sequence for Ch.heteropilicornis, hpiB2, was found. The hpiA2 banding sequence was found in all individuals, and this is its second finding after the Georgian population (Karmokov 2019). The hpiF3 banding sequence was found only in the homozygous state. Additional B-chromosomes are absent. The genetic distances (K2P) between Ch.heteropilicornis COI gene sequence from Gydan Peninsula and Norway are 1.1­–1.3%, and Georgia – 1.8%, much lower than the commonly accepted threshold of 3% for species of genus Chironomus Meigen, 1803. The phylogenetic tree for COI gene sequences estimated by Bayesian inference showed geographically determined clusters of Norway and Gydan and a separate lineage of the Georgian population of Ch.heteropilicornis. The analysis of karyotype and COI gene sequences shows that the population of Ch.heteropilicornis from the Gydan Peninsula has an intermediate position within the Ch.pilicornis group between Georgian, Yakutian and Norwegian populations. The position of Ch.pilicornis Fabricius, 1787 from Canada and Greenland on the phylogenetic tree is discussed.

Chironomus sokolovae Istomina, Kiknadze et Siirin, 1999 (Diptera, Chironomidae) is recorded from Mongolia for the first time. Eleven banding sequences determined in the Mongolian population were previously known from Altai and Yenisei populations: sokA1, sokB1, sokB2, sokC1, sokC2, sokD1, sokD2, sokE1, sokF1, sokF2 and sokG1. The additional B-chromosomes are absent. DNA-barcoding of COI gene was carried out for this species for the first time. The phylogenetic tree estimated by Bayesian inference showed a high similarity of the studied species with Ch. acutiventris Wülker, Ryser et Scholl, 1983 from the Chironomus obtusidens-group. The estimated genetic distance K2P between Ch. sokolovae and Ch. acutiventris is much lower (0.38%) than the commonly accepted threshold of 3% for species of genus Chironomus Meigen, 1803. Our results show that the accepted cytogenetic criteria of species level in the genus Chironomus are more in accordance with morphological ones of the same level, than with molecular-genetic criteria accepted for species COI genetic distance.

Chironomus sokolovae Istomina, Kiknadze et Siirin, 1999 (Diptera, Chironomidae) is recorded from Mongolia for the first time. Eleven banding sequences determined in the Mongolian population were previously known from Altai and Yenisei populations: sokA1, sokB1, sokB2, sokC1, sokC2, sokD1, sokD2, sokE1, sokF1, sokF2 and sokG1. The additional B-chromosomes are absent. DNA-barcoding of COI gene was carried out for this species for the first time. The phylogenetic tree estimated by Bayesian inference showed a high similarity of the studied species with Ch. acutiventris Wülker, Ryser et Scholl, 1983 from the Chironomus obtusidens-group. The estimated genetic distance K2P between Ch. sokolovae and Ch. acutiventris is much lower (0.38%) than the commonly accepted threshold of 3% for species of genus Chironomus Meigen, 1803. Our results show that the accepted cytogenetic criteria of species level in the genus Chironomus are more in accordance with morphological ones of the same level, than with molecular-genetic criteria accepted for species COI genetic distance.

En este estudio se caracteriza el ensamble de macroinvertebrados en bañados de desborde fluvial de cuatro arroyos pampeanos bonaerenses con diferentes actividades en el uso del suelo (intensa horticultura y ganadería extensiva) desde un punto de vista estructural y funcional. Se aplicaron índices bióticos, ecológicos, análisis multivariados y se analizaron los ensambles de oligoquetos y quironómidos. Los mayores valores diversidad y riqueza taxonómica de macroinvertebrados correspondieron al bañado de Chubichaminí (H ́= 1,9; S=19,25). Este arroyo presentó aguas ligeramente poluídas, siendo aceptable en términos de calidad del agua. El análisis multivariado ordenó a los sitios de los bañados Del Gato y Carnaval con la mayor carga de nutrientes vinculados a los taxa más tolerantes como los dípteros Stratiomyidae, Ephydridae y nematodes, oligoquetos y gasterópodos Physidae. La mayor diversidad y riqueza de oligoquetos se registró en los bañados del Cajaravillas y Chubichaminí en los meses cálidos y las diferencias encontradas se debieron principalmente a Limnodrilus hoffmeisteri Claparède, 1862. El ensamble de quironómidos estuvo conformado por 24 taxones pertenecientes a Chironominae, Orthocladiinae y Tanypodinae. El género Chironomus Meigen fue más abundante en el A° Del Gato, correspondiendo principalmente a C. calligraphus Goeldi, asociado a ambientes con evidente impacto antrópico. Los sitios estudiados mostraron diferentes patrones en la proporción de grupos funcionales alimentarios sin una clara relación con el uso del suelo. Los índices aplicados en el ensamble de macroinvertebrados resultaron efectivos para evaluar el estado ecológico de los bañados analizados.

Pollution of aquatic ecosystems with waste-water coming from tanneries is a serious challenge worldwide. The purpose of this study was to assess the water quality of Blue Nile River at a tannery in Bahir Dar, Ethiopia, using physicochemical and biological attributes. Four sampling sites were selected along the river based on the degree of degradation and major land-use types. Phyisco-chemical data, water samples, and chironomid larvae were collected monthly from March-May, 2016. Two liters of water were collected from each site and stored in the icebox and transported to Bahir Dar University. Water samples were analyzed for nutrients following standard procedures. Chironomid larvae were collected using a D- Frame net of 500 µm mesh size. One-way ANOVA was used to compare variations in all measured parameters among the sampling sites. Low dissolved oxygen (2.8 mg/l) was recorded at the site where the tannery meets the river. Moreover, the concentration of soluble reactive phosphorus, SRP (25.5±14.3 μg/l) and conductivity (1907.3±39.5 µS/cm) were low in the most upstream site of the river. A total of six Chironomid genera belonging to the subfamilies Chironominae and Tanypodinae were identified. The genus Chironomus dominated the impacted sites that had low dissolved oxygen levels. The other five genera were not found in those impacted sites. The result of this study indicated that the tannery effluent had impact on chironomid distribution as well as on river water quality.

ABSTRACT There is a long history of using insects on a decomposing corpse as an invaluable tool to estimate the minimum post-mortem interval (PMI) during death investigations. The present study was carried out to study the decomposition pattern and insects associated with a submerged rabbit (Oryctolagus cuniculus Linnaeus, 1758) carcase. A total of 1795 insect specimens were found to be associated with different decomposition stages. During the submerged fresh stage three species from the genus Chironomus visited the carcase. During the early floating and floating decay stages, insects belonging to Coenagrionidae, Chironomidae, Lestidae, Aeshnidae families along with the aquatic beetles i.e. Enochrus esuriens (Walker, 1858), Regimbartia attenuata (Fabricius, 1801), genus Helochares and Canthydrus laetabilis (Walker, 1858) visited and colonised the carcase. The advanced floating decay and sunken remains stage saw a prominence of Ranatra digitata (Hafiz and Pradhan, 1949), Ranatra filiformis (Fabricius, 1790) and genera Hydroglyphus, Hypoporus, Laccophilus, Berosus and Helochares. The Post-Mortem Submersion Interval (PMSI) was found to be longest in the winters (44 days, ADD = 1066.5) and shortest in the rainy season (16 days, ADD = 405.5) while the spring and the summer season showed a moderate PMSI of 26 days (ADD = 632.5) and 19 days (ADD = 472.5) respectively.

The study presents data on the karyotype characteristics, features of chromosomal polymorphism and the gene COI sequences of Chironomusheteropilicornis Wülker, 1996 (Diptera, Chironomidae) from the South Caucasus. We found 8 banding sequences in the Caucasian population. Overall, The Caucasian population of the species can be characterized as having a low level of polymorphism. We found one new banding sequence hpiA2 in the banding sequence pool of Ch.heteropilicornis. We observed inversion polymorphism only in the arm F. The dendrogram of genetic distances by Nei criteria (1972) shows a clear separation of the Caucasian population from populations of Siberia. At the same time, the distance between populations of Siberia and the population of South Caucasus (0.379–0.445) almost reach the mean distance (0.474 ± 0.314) between subspecies (Gunderina 2001). Due to this, we can assume that the population of South Caucasus separated from Siberian populations at the level of subspecies. Constructed on data for COI gene sequences the phylogenetic tree estimated by the Bayesian inference shows that the sequences of Ch.heteropilicornis from the South Caucasus form a separate line in the general branch of Ch.heteropilicornis sequences. At the same time, calculated K2P genetic distances between Ch.heteropilicornis sequences from Norway and Caucasus (2.0–2.2%) do not exceed the 3% threshold for the genus Chironomus.

Neonicotinoid insecticides have been shown to have high chronic toxicity relative to acute toxicity, and therefore short-term toxicity tests ≤96 h in duration may underestimate their environmental risks. Among nontarget aquatic invertebrates, insects of the orders Diptera and Ephemeroptera have been found to be the most sensitive to neonicotinoids. To undertake a more accurate assessment of the risks posed by neonicotinoids to freshwater ecosystems, more data are needed from long-term tests employing the most sensitive taxa. Using nymphs of the common New Zealand mayfly genus Deleatidium spp., we performed 28-d static-renewal exposures with the widely used neonicotinoids imidacloprid, clothianidin, and thiamethoxam. We monitored survival, immobility, impairment, and mayfly moulting propensity at varying time points throughout the experiment. Imidacloprid and clothianidin exerted strong chronic toxicity effects on Deleatidium nymphs, with 28-d median lethal concentrations (LC50s) of 0.28 and 1.36 µg/L, respectively, whereas thiamethoxam was the least toxic, with a 28-d LC50 > 4 µg/L (highest concentration tested). Mayfly moulting propensity was also negatively affected by clothianidin (during 3 of 4 wk), imidacloprid (2 of 4 wk), and thiamethoxam (1 of 4 wk). Comparisons with published neonicotinoid chronic toxicity data for other mayfly taxa and larvae of the midge genus Chironomus showed similar sensitivities for mayflies and midges, suggesting that experiments using these taxa provide reliable assessments of the threats of neonicotinoids to the most vulnerable freshwater species. Environ Toxicol Chem 2019;38:2459-2471. © 2019 SETAC.

The control of the mosquito vector Aedes aegypti L. (Diptera: Culicidae) is the main action against dengue, chikungunya, and Zika. The excessive use of conventional insecticides has promoted the development of other control methods and strategies with lower environmental impact. We evaluated the effectiveness of applying triflumuron 1ppm and emptying water-filled containers in a field trial in temperate Argentina. Both control methods were implemented either individually or combined and regularly from the beginning of the mosquito reproductive season or once it reached peak abundance. The impact on a non-target midge of the genus Chironomus was also tested. The highest reductions of Ae. aegypti were achieved in treatments which included triflumuron. This effect was stronger when applied from the beginning of the reproductive season, with < 1.3% of positive containers throughout the entire season. No enhancing effects were obtained when combining both control methods. Treatments with triflumuron were not completely innocuous for the non-target species, with Chironomus sp. more susceptible to treatments including triflumuron applied from the beginning of the reproductive season than all others. Sharp reductions of mosquito populations in urban environments with high density of water-filled containers are possible with minimum container management efforts, by applying triflumuron 1ppm every 6weeks. In temperate urban settings, better results can be obtained when applications begin early in the reproductive season of the mosquito vector Aedes aegypti.

The species compositions of the genus Chironomus in the Curonian and Vistula lagoons are very similar, represented by Ch. plumosus and Ch. balatonicus. In the Curonian Lagoon, in addition to these two species, Ch. muratensis and the first-generation interspecific hybrid Ch. muratensis × Ch. plumosus are also found. In this lagoon, Ch. plumosus occurs most frequently (84%); Ch. balatonicus is considered a subdominant species (24%). In the Vistula Lagoon, on the contrary, the high frequency of occurrence is typical of Ch. balatonicus (89%); for Ch. plumosus, it reaches only 11%. The Ch. plumosus population occupies most of the Curonian Lagoon; Ch. balatonicus is present only in its northern part, from the village of Juodkrante to the city of Klaipeda. In the Vistula Lagoon, Ch. balatonicus is distributed over almost its entire area, while Ch. plumosus is found locally, only near the mouth of the Nogat River. The distribution of the sibling species in the lagoons is determined by the salinity gradient.

The present study is an attempt to deepen the knowledge about energy patterns in a detritus-based ecosystem located within a temporary wetland, where changes of water level can affect productivity, turnover of organic matter and the flow-through energy. Energy density was directly measured using an adiabatic bomb calorimeter in samples collected in autumn, spring and summer. Dipterans belonging to the genus Chironomus were the most common and representative invertebrates within the study area. Starting from these measures, a predictive model based on the relationship between energy density and percentage of dry weight was developed, validated and applied to build a multi-annual dataset. This model was used to investigate seasonal energy density trends on longer time-scale, in relation to physical and chemical features, weather conditions and decomposition dynamics. The used approach allowed to build a 3-year dataset and to identify clear seasonal trends; moreover, the application of the model highlighted patterns in relation to precipitation regime, decomposition dynamics and the effects due to variations of these features in the investigated temporary detritus-based system over a multi-annual scale.

A revision of mapping of main and alternative banding sequences in chromosome III (EF) has been made for 14 species of the Chironomus plumosus group. In total, new versions of mapping are presented for 18 banding sequences of arm E and 18 banding sequences of arm F. A new way of tracing the origins of banding sequences in chromosome III of the Ch. plumosus group in comparison with basic banding sequences of the genus Chironomus is suggested. The presented data indicate that h’pluE2 in arm E and p’borF2 in arm F are the closest to banding sequences of Ch. piger Strenzke, 1959 and thus should be considered the most ancient among banding sequences of chromosome III in the Ch. plumosus group. Phylogenetic relationships of banding sequences of chromosome III are discussed.

Comparison of small sized and weakly chitinized structures such as the labrum (labral setae SI-SIII, labral lamella, tormal bar, pecten epipharings) and the maxilla (maxillary palp, lacinial chaeta) is provided in larvae of Chironomus plumosus, C. balatonicus, C. usenicus C. melanotus, C. acerbiphilus, and C. riparius using Scanning Electron Microscope (SEM). The general morphological structures of the labrum and the maxilla were similar in all of the Chironomus larvae. They differed only in fine details such as labral seta, mainly S I. Seta S I is always plumose on each side and differently figured: elongated in C. balatonicus, C. plumosus, C. melanotus and C. usenicus; rounded in C. acerbiphilus and C. riparius. Some differences were also observed in the shape, length or ratio of lacinial chaetae (LCh I, LCh II). Based on morphological variation in the larvae of some Chironomus species, results indicated that the SEM method is apparently beneficial and useful in the analysis of smaller and weakly chitinized morphological structures such as the labrum and the maxilla.