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Species Chironomus sp. prope agilis Kiknadze, Siirin, Filippova et al., 1991 belongs to the Ch. plumosus group of sibling species. It was described on the basis of its karyotype and analysis of isozymes from one population in the Urals but since then no quantitative data on chromosomal polymorphism of this species have been published. The goal of this study is to broaden our knowledge of the chromosomal polymorphism and distribution of the Chironomus sp. prope agilis, which, along with the data on chromosomal polymorphism of other species from the Ch. plumosus group, can give us a better understanding of the connection between chromosomal polymorphism and ecological conditions of habitats. The specimens of Chironomus sp. prope agilis were found only in 8 natural populations from the Urals, Western Siberia and Kazakhstan, which allows us to conclude that the species range of Chironomus sp. prope agilis is not as wide as for most other species from Ch. plumosus group. An analysis of chromosomal polymorphism in these 8 natural populations of Chironomus sp. prope agilis has been performed. All of the studied populations were either monomorphic or showed very low level of chromosomal polymorphism, with 4.4–8.7% of heterozygous specimens per population and 0.04–0.08 heterozygotic inversion per larvae. The total number of banding sequences found in the banding sequence pool of Chironomus sp. prope agilis is 10. The mapping of banding sequence p’ag2B3 is presented for the first time. Besides inversions, one reciprocal translocation was found in a population from Kazakhstan, B-chromosome was found in one population from the Urals region of Russia, and heterozygosity of the level of expression of Balbiany rings in arm G was observed in several studied populations.

During the summer of July to September 2020, a biodiversity survey on Chironomidae of Baishanzu Nature Reserve, China was made. In total, five Stenochironomus taxa/species were discovered, of which two belong to undescribed species and one (S. okialbus Sasa, 1990) is reported for the first time from China. The male adults of two new species are described and illustrated. Stenochironomus annulus Song & Qi sp. nov. is distinguished in having a wing with two dark spots restricted to the fork area of FCu and RM, the mid- and hind-femur each with a brown annulus, and the inferior volsella with two setae and one strong terminal spine. Stenochironomus baishanzuensis Song & Qi sp. nov. is distinguished by a combination of characters: a single dark spot on the middle part of the wing, fore legs brown to dark brown except for the basal 3/4 of femur, and the inferior volsella with four long setae and one stout terminal spine. The neighbour-joining tree based on public COI barcodes formed distinct clades with clear support for the new species. An updated key to known male adults of Stenochironomus from China is also provided.

A new species of the genus Polypedilum Kieffer, 1912 is described from Baishanzu Nature Reserve, China, based on molecular and morphological data. Molecular phylogenetic analysis based on standard barcode sequences confirmed a new clade of Polypedilum (Collartomyia) species. The new species is easily distinguished from its congeners by a combination of the following morphological characters: membrane of wing with a large spot occupying 70% of the proximal area; tergite without dark brown band pigmentation; tarsi I–V dark brown; superior volsella with three outer lateral setae and six long setae along inner base; inferior volsella with setose tubercules. An updated key to adult males of the subgenus Collartomyia is also provided.

Larval stages of the Chironomidae (Diptera) can be found in almost any aquatic habitat, includ- ing artificial lakes. They form an important fraction of the macrozoobenthos of most freshwater ecosystems. The Mavrovo reservoir as an artificial lake in the Republic of Macedonia, to date, has never been an object of hydrobiological research of this type. For that reason, the purpose of this study was to conduct research on the composition and structure of the chironomid larvae fauna that inhabits the Mavrovo reservoir. The quantitative samples for this research were collected during one year (2017/18), seasonally from five different localities (T1–T5) – T1-Ulazna, T2-Hotel Radika, T3-Middle of the reservoir, T4-Bunec, and T5-Old church (village Mavrovo). According to the results, Chironomidae was represented with five subfamilies, two tribes, and 25 taxa. The subfamilies are Chironominae with the two tribes Chironomini and Tanytarsini, Tanypodinae, Orthocladiinae, Diamesinae, and Prodiamesinae. The dominant taxon is Tanytarsus sp., and besides it, the following taxa: Procladius sp., Chironomus plumosus, Harnischia sp., Polypedilum nubeculosum, and Orthocladius saxicola are characterized by greater community participation. The highest density of chironomid larvae fauna was recorded during the summer, a total of 1013.69 ind/m2, compared to the lowest registered in the spring season which is only 9.78 ind/m2.

Karyotype characteristics and gene COI sequences of Chironomus bonus Shilova et Dzhvarsheishvili, 1974 (Diptera, Chironomidae) from the South Caucasus (Republic of Georgia, Paravani river)

Karyotype and COI gene sequences of Chironomus melanotus Keyl, 1961 from the Yaroslavl region (Russia) were analyzed. A low level of chromosomal polymorphism has been confirmed, eventually eight banding sequences were found: melA1, melB1, melC1, melD1, melE1, melF1, and melG1; only melD2 was found in two larvae from the Sunoga river. Analysis of phylogenetic tree and estimated genetic distances has shown not all COI gene sequences of Ch. melanotus in GenBank and BOLD to belong to this species. The lower distance of 0.4% was observed between two sequences from the Yaroslavl region and Finland, apparently these are true Ch. melanotus sequences. The distances between true Ch. melanotus and other sequences from Finland were 9.5% and 12.4%, and from Sweden it was 11%. The average genetic distance between studied sequences of 9.1% is out of the range of the 3% threshold previously determined for chironomids. According to our estimates, there are two sequences with a distance of 2.9% that may belong to Ch. annularius Meigen, 1818, and one sequence with a genetic distance of 2.1%, may belonging to Ch. cingulatus Meigen, 1830, which has been confirmed karyologically. Another two sequences form a separate cluster. We suggest that they either belong to a known species, but are not present in the databases, or belong to a distinct, undescribed species.

Quantitative and qualitative analysis of chromosomal polymorphism in 19 natural populations of Ch. agilis had been performed. Most studied populations showed a medium level of chromosomal polymorphism: on average 45±3.0% of specimens are heterozygotes with 0.52±0.01 heterozygotic inversion per larvae. Besides inversions, B-chromosomes were found in two populations. The total number of banding sequences found in banding sequence pool of Ch. agilis is 16. Three banding sequences – p’agiB3, p’agiD3, p’agiF3 – are described for the first time.

The karyotype features and gene COI sequence of Chironomus heteropilicornis 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.

Kribiodosis Kieffer, 1921, an African genus of Chironomini (Diptera: Chironomidae), is newly recorded from the Oriental region through a new species K. cantonensis sp. n. Detailed descriptions of the male, female and a DNA barcode are provided. With the inclusion of the new species bearing scutal tubercle and fused tibial comb, the generic diagnosis needs revision and expansion. The phylogenetic position of Kribiodosis within the tribe Chironomini is explored based on five concatenated genetic makers (18S, 28S, CAD1, CAD4 and COI-3P) using both mixed-model Bayesian inference and maximum likelihood methods. Kribiodosis is placed as a core member of the Microtendipes group but its precise sister group remains unclear. Inclusion of the analysis of Nilodosis Kieffer, another Chironomini genus with an African-Oriental distribution, reveals an unexpected robust position as sister to a large and diverse inclusive group of many Chironomini.

Puerto Viejo es un humedal costero de importancia para aves residentes y migratorias conformado por varios cuerpos de agua estacionales, naturales y artificiales con altas salinidades. Este ecosistema se encuentra ubicada al sur de Lima, Perú. En junio de 2004 se llevaron a cabo censos de la biodiversidad y abundancia de la comunidad de invertebrados, representando a diferentes cuerpos de agua en 28 estaciones de muestreo litorales distribuidas en cinco lagunas dispersas en toda el área pantanal representando la heterogeneidad espacial del humedal. La distribución de las estaciones por laguna fue: laguna 1 (n=2): estaciones 1 y 2; laguna 2 (n=5): estaciones 3 al 7; laguna 3 (n=6): estaciones 8 al 13; laguna 4 (n=9): estaciones 14 al 22, y finalmente la laguna 5 (n=6): estaciones 23 al 28. Las muestras fueron colectadas usando una red de plancton de 75 de diámetro y preservadas empleando una solución de formol azucarado al 4 %. En adición, fueron determinados algunos parámetros limnológicos como conductividad (Ohms•cm-2), coeficiente de extinción, temperatura del agua (°C), temperatura del aire (°C) en cada punto de muestreo. Los resultados indicaron la presencia de 40 taxa, siendo más abundantes y frecuentes los rotíferos Brachionus calyciflorus (Pallas, 1776) y Lecane lunaris (Ehrenberg, 1831), el nematodo Rhabdolaimus sp, De Man, 1980, el copépodo Cyclops strennus (Fisher, 1851), el insecto Chironomini y el foraminífero Globoratalia scitula Brady, 1877. El número de organismos por litro (N° org. L-1) fue de 14 (4-45) y el número de taxa por estación de muestreo fue de 10 (5-20). El índice de diversidad promedio de Shannon-Wiener fue relativamente alto. Los índices de similaridad mostraron valores mayores al 30% de similaridad entre las 28 estaciones de muestreo. Se concluye que 37 de los 40 taxa son registros nuevos para el humedal de Puerto Viejo, Lima, Perú.

There is much left to learn about the diversity of Chironomidae in Brazil. To help to resolve this problem, a preliminary study of the Chironomidae present in a stream located in center of Brazil was proposed. The aim of this research was to provide a first record of the Chironomidae assemblage at Sarandi stream, in the Brazilian Cerrado. Samples were taken using a handheld D-net from the stream in October 2009. The samples were transported to the laboratory where the material was processed and the Chironomidae specimens were slide mounted, counted and identified to genera. Ninety individuals belonging to 15 genera were found, Chironomini was the richest tribe, with seven genera, while Tanytarsini showed the highest abundance of individuals (55.6%). Overall, Rheotanytarsus (20%), Tanytarsus ortoni-group (16.7%) and Lopescladius (14.4%) were the most abundant genera.

Polypedilum (Cerobregma) huapingensis Liu & Lin, sp. nov. is described and illustrated based on an adult male from Huaping National Nature Reserve, Guangxi, China. A DNA barcode analysis, including the known partial COI sequences of species in the Cerobregma subgenus, was conducted. An updated key to adult males of the subgenus Cerobregma is provided.

The immature stages of the New Zealand endemic Paucispinigera Freeman and Paraborniella Freeman, endemic to Australia, are described fully for the first time. A new species of Paratendipes Kieffer endemic to Australia is described in all life stages. Morphological support from larvae for placement in a ‘Microtendipes’ group in tribe Chironomini includes the 6-segmented antenna with Lauterborn organs on the 2nd and 3rd segments, and a well-demarcated, multi-toothed ventromentum. The pupa has a few-branched thoracic horn and the distribution of taeniate L-setae is informative. Significant differentiating characters of the adult male include the form of tibial apices and the structures of superior and median volsellae in the genitalia. In the wing of Paucispinigera, the squama lacks setae, contrary to the original description, and unusually has vein M1+2 setose in both sexes and also the M3+4 setose in the female. An apical spine on the gonostylus of Paucispinigera is unusual. The female genitalia are described here for the first time but lack phylogenetically informative variation. An Australian species of the widespread genus Paratendipes Kieffer, described here as Paratendipes sinespina sp. n., is provided for comparison. Paucispinigera and Paraborniella each warrant independent generic rank.

Expanded generic diagnoses of all life stages of Yaeprimus Sasa et Suzuki, 2000 (Lunditendipes Harrison, 2000, syn. n.) are given. Yaeprimus tropicus comb. n. is redescribed as an adult based on type material. Additionally, a new species Y. balteatus sp. n. from Oriental China is described based on the adult male and pupa. The phylogenetic position of Yaeprimus within Chironomini and the validity of the new species are explored based on concatenated five genetic markers (18S, 28S, CAD1, CAD4, and COI-3P) through both mixed&ndash, model Bayesian inference and maximum likelihood methods. The results strongly support Yaeprimus as sister to Imparipecten Freeman, 1961, which counters a previously proposed systematical position based solely on morphology.

Riethia Kieffer, a genus of the non-biting midge subfamily Chironominae (Diptera: Chironomidae) is distributed in Australia, New Zealand, New Caledonia and South America. This austral distribution could be due to earth history (vicariance) or from Southern Hemisphere dispersal(s). We obtained samples from each area, most intensively from throughout Australia. We included putative sister genus Pseudochironomus Malloch, many genera from tribe Tanytarsini, enigmatic taxa in Chironomini and conventional outgroups from other subfamilies. We assembled a multilocus molecular dataset for four genetic regions from 107 individuals to reconstruct the first dated molecular phylogeny for the group. Four terminal clusters corresponded to unreared (thus unassociated) larvae. Monophyly was supported for ‘core’ Riethia, Pseudochironomus, putative tribe Pseudochironomini, tribe Tanytarsini (including enigmatic Nandeva Wiedenbrug, Reiss & Fittkau) and subfamily Chironominae. All species are monophyletic except for R. cinctipes Freeman, which includes R. neocaledonica Cranston. Riethia zeylandica Freeman, previously thought to be widespread in eastern Australia, now is a New Zealand endemic with Australian specimens allocated now to several regionally restricted species. The origin of Riethia was at 60.6 Ma (‘core’) or 52.1 Ma depending on the relationship of two South American species. Both dates are before the break-up of South America and Australia. Diversification within crown group Riethia started before the Cretaceous–Paleogene boundary, with subsequent separation at 52 Ma of an Australian ‘clade I’ from its sister ‘clade II’, which comprises Australian, New Zealand and New Caledonian species. Inferred dates for species origins of New Caledonia and New Zealand taxa imply transoceanic dispersals from eastern Australia. Western Australian species diverged during the mid to late Miocene from their eastern Australian sister taxa. This correlates with the onset of drying of Australia and the separation of mesic east from west by the formation of an arid proto-Nullarbor. Taken together, the inferred tempo of diversification in the group included both older ages reflecting earth history, yet with suggested recent intra-Pacific separations due to transoceanic dispersals.

The phenomenon of water pollution constitutes a massive threat to the very existence of freshwater bodies and can potentially eliminate vital benefits otherwise associated with these resources. In several countries such as Ghana, initial steps to salvage existing freshwater bodies have given rise to the need for effective water quality assessment and biological monitoring. This study was conducted with the aim of assessing the abundance, composition, and diversity of benthic macroinvertebrate fauna in the Nima Creek, situated in Accra, Ghana. On the basis of findings in relation to identified macroinvertebrate types, we further determine the quality of water in the creek. Samples were collected at 8 different riffles with a Surber sampler. The benthic macroinvertebrates sampled consisted of 6 taxa and 5891 individuals belonging to Nematoda, Oligochaeta, Gastropoda, and Insecta classes. Chironomini were the predominant group with 99.04% on the average, followed by Psychoda sp (0.44%), Rhabitidae (0.26%), and Tubifex (0.26%) at the upstream stretch of the creek. The downstream was dominated by Chironomini forming 97.30% on the average, followed by Tubifex (1.52%), Rhabitidae (1.08%), and Psychoda sp (0.05%). The estimated diversity of the sampling area for both upstream and downstream was assessed by using the Simpson Diversity Index and was found to be 0.53, indicative of a fairly diversified community structure. Family Biotic Index (FBI) was used to determine the water quality of the creek and found to be 9.92, which indicates severely polluted water. One-way analysis of variance (ANOVA) revealed no significant differences between upstream and downstream abundances at both 95% and 99% confidence levels. However, Melanoides tuberculata was found only at the downstream reach due to low current, the formation of rocky substratum, and the absence of riparian vegetation making it a suitable habitat.

The genus Fleuria Kieffer, 1924 is recorded from China for the first time. The male and female of F. lacustris Kieffer, 1924 are redescribed and illustrated, and the sexes are associated by standard DNA barcodes.

In this study, theOlezoa stream in Yaounde was assessed todetermine the morphological structure of Chironomid genera that are present in the aquatic ecosystem. The biological analysis revealed a lowdiversity of larva andpupalexuviae. The tribe of Chironomini revealed 03 genera which are: Chironomus, Goeldichironomus and Nilothauma. The chironomidae developmental stages exhibit a variety of adaptations in polluted areas which could be: morphological, physiological and behavioral all of them occurring simultaneously within each developmental form and the different genera. Gelatinous egg masses which were found floating on the surface of water or attached to the aquatic vegetation of Obili Lake have an elongated- ribbon like shape. Each mass possesses an average of 50 ± 7 egg rows arranged linearly; with each egg row containing an average of 16.8 ± 1 eggs. Each egg has an oval shape with a characteristic brown colour. It measures between 4.32-4.96mm in length with an average length of 4.73±0.25mm in the samples assessed.Read Complete Article at ijSciences: V62017031226 AND DOI: http://dx.doi.org/10.18483/ijSci.1226

Identification keys are provided for the final (4th) instar larvae of genera of Chironomidae (Diptera), from aquatic habitats in Australia and New Zealand. Morphological features of taxonomic utility are discussed and illustrated by line drawings. Summaries of described species for each genus and their distribution is provided, with reference to means of further identification where available. In the subfamily Podonominae, 5 genera are keyed of which 3 are recorded from New Zealand; the 4 genera of Aphroteniinae are from Australia (absent from New Zealand); in Diamesinae 1 genus is Australian, 2 are from New Zealand; in the Tanypodinae 21 genera are found in Australia and 4 are from New Zealand; in Orthocladiinae 31 genera are reported from Australia, 14 from New Zealand; and in Chironominae 43 genera are keyed from Australia, 9 from New Zealand. Larvae of Axarus Roback, Chernovskiia Sæther and Omisus Townes (Chironomini) are recognised in Australia for the first time. The undescribed larva of Paucispinigera Freeman, endemic to New Zealand, is keyed and several other New Zealand taxa are included based on unpublished records. Genera reported from Australia and New Zealand as adults, but unknown as larvae, are listed.

Aedokritus platycnemis Edwards, previously known from northeastern Argentina, is redescribed based on holotype and additional material from Brazil. Axarus cordiformis sp. n. is described and figured, based on a male adult collected in Brazilian Amazon. Aedokritus coffeatus Trivinho-Strixino, Aedokritus souzalopesi Oliveira & Messias, Axarus globosus Donato, Mauad & Andersen, Axarus intervales Andersen, Mendes & Hagenlund and Axarus diabolicus Andersen, Mendes & Hagenlund have their distribution extended.

Descriptions of two Chironomini pupal types collected in Yunnan Province are given. Among known genera, both types closely resemble that of the North American Hyporhygma Reiss, 1982, but the spine and spinule pattern of the dorsal abdomen does not fit within the current taxonomic boundaries, and represent an endemic component in the Oriental region. A new genus description is expected when associated adults are available.

A new species of Chironomus Meigen, C . rishii (Diptera: Chironomidae: Chironominae) from Brazil, is described and figured as adults male and female, pupa and larva. Adults of C . rishii sp. n. can be recognized by the prominent scutal tubercle and the hypopygium with narrow, elongated and strongly hooked superior volsella. Pupae of this new species are indistinguishable from most of the described Neotropical species, while larvae may be separated by the mentum with deeply incised trifid median tooth and 7 pairs of lateral teeth and the absence of lateral and ventral tubules. This last feature would place C . rishii sp. n. within the 'salinarius group'. However, this is not a group in the systematic sense, but an artificial grouping equivalent to a morphotype that reflects only the tubule character state. It is suggested that the absence of tubules is an adaptation for tolerating a wide range of salinity levels, however the 'salinarius group' had been also recorded in freshwater environments. Here, larvae without abdominal tubules were found in an environment with low levels of salinity, which indicates that the tubule condition may be result of further abiotic pressures, and configures a rather enigmatic scenario to this feature, particularly when considered the fact that larvae of Chironomus having tubules had also been recorded at the same habitat, living under similar conditions of C. rishi sp. n.

Kribiodorum Kieffer, an otherwise North American and African genus of Chironomini (Diptera: Chironomidae), extends to the Oriental region through two new species. An adult male and female of Kribiodorum malicky sp. n. is newly described from Thailand, and from Brunei (Borneo) a pharate male and the pupa of Kribiodorum belalong sp. n. is described. Additionally, from Namibia (s.w. Africa) a 'manuscript' taxon is described formally with co-authorship of the late Arthur Harrison as Kribiodorum kunene sp. n. Males of the new species and the sole new pupa conform substantially to generic diagnoses based on the North American Kribiodorum perpulchrum (Mitchell). Examination of specimens of African Kribiodorum pulchrum Kieffer and N. American K. perpulchrum confirms their morphological similarity and reaffirms the junior synonymy of Stelechomyia Reiss designated for the North American species. Kribiodorum expands the number of genera of Chironomidae with African and Asian representatives, although unusual in its absence from Australia yet presence in the Nearctic.

Three new species of non-biting midges of the tribe Chironomini, Polypedilum (s. str.) odyrensis sp.n., Polypedilum (s. str.) servatum sp.n., Robackia lukini sp.n., are described on the morphology of imago males collected on the streams of the Bolshekhekhtsyrsky Nature.

Skusella Freeman, 1961 (Diptera: Chironomidae, Chironominae), known previously from adults from Australia and Africa, is revised with extended descriptions, including for immature life stages. Skusella is diagnosed based on its type species S. subvittata (Skuse, 1889) from Australia, S. pallidipes (Kieffer, 1921) from the Afrotropical region (the only other originally included species), a second African species S. freemani Harrison, 2002, and S. silingae Tang, sp. n., newly described here from the pupa and adult males from China. The immature stages of Skusella have been known informally for several decades, notably for a characteristic fringe of setae on one or more abdominal pleurae of the pupa, shared only with newly described Paraskusella Cranston, 2018 within the Chironominae. Amongst larvae of Chironomini with 6-segmented antenna, alternate Lauterborn organs and a well-demarcated ventromentum, those of Skusella are distinguishable only with caution due to insufficient reared associations. Unassociated pupal exuviae, tentatively belonging to three unknown new species, are described informally from China, as is a larval type from Africa. Range extensions include for S. freemani, with pupae (newly described here) from Nigeria and Cameroon, at least 5000 km from the type locality in South Africa. A wider distribution of S. subvittata in Australia and Asia is revealed by extensive pupal exuviae sampled from drift.

Mitochondrial DNA sequences from cytochrome c oxidase subunit I (COI) were used to provide a phylogeny of the Chironomidae (Diptera) from Turkey. Data were obtained from 70 species of Chironomidae belonging to the genera Ablabesmyia, Chironomus, Cladotanytarsus, Conchapelopia, Cricotopus, Cryptochironomus, Dicrotendipes, Endochironomus, Eukiefferiella, Kiefferulus, Macropelopia, Micropsectra, Microtendipes, Paracladopelma, Paracricotopus, Paratanytarsus, Paratendipes, Paratrichocladius, Polypedilum, Psectrocladius, Psectrotanypus, Rheocricotopus, Tanytarsus, Thienemannimyia, Virgatanytarsus and Zavrelimyia. Neighbour-joining (NJ) and maximum likelihood (ML) analyses were used to identify the relationships among species. We confirmed monophyly of all sampled subfamilies and also tribes Chironomini, Tanytarsini, Macropelopiini and Pentaneurini, with the exception of subfamily Tanypodinae in ML analysis. However, in Chironomini, genus Chironomus, Cryptochironomus, Endochironomus and Paratendipes were monophyletic, while Polypedilum was not. Likewise, in Tanytarsini, genus Paratanytarsus and Cladotanytarsus were monophyletic, while Tanytarsus and Micropsectra were not. Also, in Macropelopiini and Pentaneurini, genus Macropelopia and Zavrelimyia were monophyletic. However, Ablabesmyia, genus of Pentaneurini, formed monophyletic group only in NJ analysis. In this study, we determined an unexpected inclusion of a Tanytarsus brundini individual into Micropsectra group. According to our pairwise distance analyses, the mean interspesific divergence was 19.4% for all species studied. (C) 2015 Elsevier Ltd. All rights reserved.

Spates of different magnitude in a four order section of the lowland Drzewiczka River (central Poland) downstream from a dam reservoir and a wild-water slalom canoeing track (abbr. WCT) located just below the dam were studied. For over 20 years daily fluctuations enabling the training of canoeists induced a patchy mosaic of the riverbed, with five dominant habitats: pool, stagnant with emergent plants, submersed macrophyte, bank and riffle. Artificial floods, in September 2000, March 2001 and February 2002, were other flow events of this reach, thus the main aim of this paper is to assess the resistance of macroinvertebrates, measured as the relative lack of loss in density after floods.The three- (September) and five-fold (March) increased discharge in relation to the median affected the riverine environmental variables and caused the entrance into the water column and/or washing away of Ephemeroptera, Trichoptera and Simuliidae. In turn the highest-flow event (February, 16-fold flow increase) induced the instability of all bed patches. Oligochaeta, one of the dominant, inbenthic groups of passive drifters, were dragged along the bottom and then stopped by macrophytes. Meanwhile, chironomids, the second dominant benthic group, showed two kinds of behaviour patterns. Orthocladiinae, organisms prone to drift, were washed away after each flood; consequently the riffle and submersed macrophytes became partly depleted of them. Other midges, inbenthic Chironomini (Chironominae) with worse propensities to drift, were also washed out, except from deeper sediment layers, between the roots of macrophytes and in the bank habitat. Thus the macroinvertebrate assemblages in the Drzewiczka River have adapted to the moderate pulse disturbances, but their response to high flow events depends on the species' traits.

We measured sediment methane (CH4) efflux and CH4 oxidation in intact sediment cores from 17 arctic Alaskan lakes which varied in lake area and depth. We evaluated the relationships between CH4 oxidation and lake area, depth, and hypolimnetic dissolved oxygen (DO). We also evaluated the relationship between δ13C of larval Chironomini and CH4 oxidation and estimated use of methane-derived carbon (MDC) by larval Chironomini. CH4 oxidation declined exponentially as hypolimnetic DO increased, and Chironomini δ13C declined exponentially as CH4 oxidation increased. Mixing model estimates indicated that Chironomini incorporated 0% to 40% MDC between study lakes, dependent on CH4 oxidation. These estimates overlap broadly with those reported for eutrophic lakes, illustrating that use of MDC is not strictly related to lake productivity, but instead is determined by factors controlling hypolimnetic DO and facilitating CH4 oxidation at the sediment–water interface. In the lakes studied here, hypolimnetic DO was determined by basin characteristics. Our results, viewed in the context of other studies elsewhere, illustrate that CH4 oxidation is a potentially important process supporting consumer production across the full spectrum of lake productivity.

Understanding past methane dynamics in arcticwetlands and lakes is crucial for estimating future methane release. Methane fluxes from lake ecosystems have increasingly been studied, yet only few reconstructions of past methane emissions from lakes are available. In this study,we develop an approach to assess changes in methane availability in lakes based on δ13c of chitinous invertebrate remains and apply this to a sediment record from a Siberian thermokarst lake. Diffusive methane fluxes from the surface of ten newly sampled Siberian lakes and seven previously studied Swedish lakes were compared to taxon-specific δ13c values of invertebrate remains from lake surface sediments to investigate whether these invertebrates assimilated 13C-depleted carbon typical for methane. Remains of chironomid larvae of the tribe Orthocladiinae that, in the study lakes, mainly assimilate plant-derived carbon had higher δ13c than other invertebrate groups. δ13c of other invertebrates such as several chironomid groups (Chironomus, Chironomini, Tanytarsini, and Tanypodinae), cladocerans (Daphnia), and ostracods were generally lower. δ13c of Chironomini and Daphnia, and to a lesser extent Tanytarsini was variable in the lakes and lower at sites with higher diffusive methane fluxes. δ13c of Chironomini, Tanytarsini, and Daphnia were correlated significantly with diffusive methane flux in the combined Siberian and Swedish dataset (r1=-0.72, p = 0.001, r = 0.53, p = 0.03, and r1\4;0.81, p < 0.001, respectively), suggesting that δ13c in these invertebrates was affected by methane availability. In a second step, we measured δ13c of invertebrate remains from a sediment record of Lake S1, a shallow thermokarst lake in northeast Siberia. In this record, covering the past ca 1000 years, δ13c of taxa most sensitive to methane availability (Chironomini, Tanytarsini, and Daphnia) was lowest in sediments deposited from ca AD 1250 to ca AD 1500, and after AD 1970, coinciding with warmer climate as indicated by an independent local temperature record. As a consequence the offset in δ13c between methane-sensitive taxa and bulk organic matterwas higher in these sections than in other parts of the core. In contrast, δ13c of other invertebrate taxa did not show this trend. Our results suggest higher methane availability in the study lake during warmer periods and that thermokarst lakes can respond dynamically in their methane output to changing environmental conditions.

The immature stages are described for the first time for Chironomus (Xenochironomus) australiensis Freeman (Diptera: Chironomidae) and the adult male is redescribed including from type specimens. The species does not belong to Chironomus Meigen or Xenochironomus Kieffer, but is best placed in a modestly expanded Einfeldia Kieffer. Application of this genus name is clarified, including by a lectotype fixation for its type species, E. pectoralis Kieffer, 1924. Einfeldia australiensis (Freeman) comb. n. provides the first record of the genus from Australia; otherwise the genus is reported confidently only from North America, Central America and western Europe to Japan. The immature stages of E. australiensis occur in relatively shallow mesotrophic to eutrophic dune lakes and maars with circum-neutral pH and high conductivity, from southeastern Queensland to southern Australia. The cytology is described briefly from larval salivary glands. Alternative genus placements for the species are discussed, and problems with Einfeldia and connected systematics in the tribe Chironomini are addressed.

During our work on the Chironomidae chapter of the forthcoming Manual of Afrotropical Diptera we examined type material of the four Chironomini species Chironomus (Endochironomus) hamatus, Chironomus (E.) pruinosus, Chironomus (E.) woodi and Chironomus (Cryptochironomus) inflexus described by Paul Freeman. We provide photos of the types and associated material and argue for the following generic placements: Chironomus (Benthalia) hamatus comb.n., Kiefferulus pruinosus comb. n., Synendotendipes woodi comb. n. and Cladopelma inflexum. Open Access article. This work is licensed under a Creative Commons Attribution 4.0 International License.

SUMMARY 1. Methanogenic carbon can be incorporated by methane-oxidising bacteria, leading to a 13 C-depleted stable carbon isotopic composition (d 13 C) of chironomids that feed on these microorganisms. This has been shown for the chironomid tribe Chironomini, but very little information is available about the d 13 C of other abundant chironomid groups and the relationship between chironomid d 13 C and methane production in lakes. 2. Methane flux was measured at the water surface of seven lakes in Sweden. Furthermore, fluxes from the sediments to the water column were measured in transects in two of the lakes. Methane fluxes were then compared with d 13 C of chitinous chironomid remains isolated from the lake surface sediments. Several different chironomid groups were examined (Chironomini, Orthocladiinae, Tanypodinae and Tanytarsini). 3. Remains of Orthocladiinae in the seven study lakes had the highest d 13 C values ()31.3 to )27.0&), most likely reflecting d 13 C of algae and other plant-derived organic matter. Remains of Chironomini and Tanypodinae had lower d 13 C values ()33.2 to )27.6& and )33.6 to )28.0&, respectively). A significant negative correlation was observed between methane fluxes at the lake surface and d 13 C of Chironomini (r = )0.90, P = 0.006). Methane release from the sediments was also negatively correlated with d 13 C of Chironomini (r = )0.67, P = 0.025) in the transect samples obtained from two of the lakes. The remains of other chironomid taxa were only weakly or not correlated with methane fluxes measured in our study lakes (P > 0.05). 4. Selective incorporation of methane-derived carbon can explain the observed correlations between methane fluxes and d 13 C values of Chironomini. Remains of this group might therefore have the potential to provide information about past changes in methane availability in lakes using sediment records. However, differences in productivity, algal d 13 C composition and the importance of allochthonous organic matter input between the studied lakes may also have influenced Chironomini d 13 C. More detailed studies with a higher number of analysed samples and detailed measurement of d 13 C of different ecosystem components (e.g. methane, dissolved inorganic carbon) will be necessary to further resolve the relative contribution of different carbon sources to d 13 C of chironomid remains.

We provide the first highly sampled phylogeny estimate for the dipteran family Chironomidae using molecular data from fragments of two ribosomal genes (18S and 28S), one nuclear protein-coding gene (CAD), and one mitochondrial protein-coding gene (COI), analysed using mixed-model Bayesian and maximum likelihood inference methods. The most recently described subfamilies Chilenomyiinae and Usambaromyiinae proved elusive, and are unsampled. We confirm monophyly of all sampled subfamilies except Prodiamesinae, which contains Propsilocerus Kieffer, previously in Orthocladiinae. The semifamily Chironomoinae is confirmed only if Telmatogetoninae is included, which is closer to Brundin's original suggestion. Buchonomyiinae is excluded from Chironomoinae: it is a sister group to all remaining Chironomidae, conforming more to Murray and Ashe's argumentation. Semifamily Tanypodoinae is a grade and unsupported as monophyletic: the austral Aphroteniinae alone is sister to all Chironomidae (less Buchonomyiinae). Podonominae is weakly supported as the next sister group, in contrast to some estimates that place this subfamily as sister group to Tanypodinae alone. In Diamesinae, the southern African Harrisonini is confirmed as a member, but embedded within austral tribe Heptagiini, which is confirmed as sister to the undersampled Diamesini. Tribe Pentaneurini and ‘non-Pentaneurini’ taxa are reciprocally monophyletic in Tanypodinae. Recent molecular findings concerning Podonominae are substantiated, with a monophyletic tribe Podonomini, Boreochlini forming a grade and Lasiodiamesa Kieffer placed as sister to all other Podonominae, but with uncertainty. In Orthocladiinae, a postulated two-tribe system of Orthocladiini and Metriocnemini can be supported after exclusion of a Corynoneura group and a Brillia group, which is revealed as sister to Stictocladius Edwards. The marine Clunio Haliday and Thalassosmittia Strenzke & Remmert (given high rank in the past) are clearly embedded deep in Orthocladiinae. The finding of Shangomyia Saether & Wang + Xyiaomyia Saether & Wang as sister group to all other Chironominae justifies high rank, as their authors suggested. Pseudochironomini (untested by sampling shortfall) is sister to a monophyletic Tanytarsini (with a weakly supported inclusion of the enigmatic Nandeva Wiedenbrug, Reiss & Fittkau). The tribe Chironomini can be supported only by excluding Shangomyia + Xyiaomyia, and a postulated monophyletic clade comprising several taxa such as Microtendipes Kieffer, with six-segmented larval antennae and alternate Lauterborn organs, that is sister group to Pseudochironomini + Tanytarsini. The tempo of diversification of the family, deduced by divergence time analysis (beast), shows Permian origination with subfamily stem-group origination from the mid–late Triassic to the early Cretaceous. Crown-group origination ranged from Podonominae on a short stem originating in the mid Jurassic to long-stemmed Aphroteninae from the late Cretaceous. Node dates allow inference of some vicariance via Gondwanan fragmentation, including certain nodes involving southern Africa.

This is the first study to infer the phylogenetic structure of minges of the subfamily Chironominae from the amino acid sequence of cytochrome oxidase I (COI). The subdivision of Chironominae into two tribes, Chironomini and Tanytarsini, has been confirmed. The segregation of the genera Pseudochironomus and Riethia into a separate tribe has not been confirmed. Stenochironomus gibbus forms a branch considerably deviating from the subfamily Chironominae. The genus Micropsectra is formed by a large polyphyletic cluster that also includes the genera Virgotanytharsus, Reotanytharsus, Kenopsectra, and Parapsectra. Tanytarsus is the basal genus of the tribe Tanytarsini. The times of divergence of the main taxa of Chironominae have been estimated. The calculated time of divergence of the genus Chironomus disproves the assumption that it is phylogenetically old.

In an attempt to arrive at a preliminary reconstruction of the limnic food web of the Upper Miocene Bicorb Basin (Eastern Spain), and to obtain new palaeontological information regarding the salinity of its palaeolake, studies were made of the fossil assemblages of aquatic organisms in the outcrops of facies associations 2 and 3 (subunit b of the upper unit, established in 1998 by Anadon et al.) These outcrops (known as Venus, Cantera and Bicorb Insectos-1 and -3) are typical Konservat-Lagerstatten. We here describe four specimens of a new species of the cyprinodontid genus Aphanius ( A. bicorbensis sp. nov.) plus several chironomid insects and coprolites, mainly from the Venus outcrop. Two morphotypes of chironomid pupal exuviae were found, both of which were attributed to the subfamily Chironominae. The larger morphotype was attributed to Chironomus sp. (tribe Chironomini) and the smaller to Tanytarsini gen. et sp. indet. Coprolites were separated into two types – C1 and C2 – based on their contents, i.e., the remains of chironomids or miliolid foraminifers respectively. The miliolid foraminifers belonged to the family Hauerinidae, possibly to the genus Quinqueloculina . It is concluded that Aphanius fish were second level consumers, feeding on chironomids and miliolid foraminifers. Primary producers were mainly represented by the aquatic plant Potamogeton , Botryococcus green algae, and microbial mats (almost certainly photosynthetic). This notably simple limnic food web and this aquatic fossil assemblage suggest that the Bicorb palaeolake was saline or brackish; the living taxa related to this assemblage are notably tolerant of high salinity. This salinity is related to the presence of a Triassic diapir on the southern side of the Bicorb Basin. In addition, non-bioturbated, finely laminated calcareous mudstones and exceptionally well-preserved delicate insects indicate the lake water to have shown a halocline (leading to meromictic episodes), with the development of microbial mats at the lake bottom.

A Study of the chironomid community was undertaken in Lake Łękuk Wielki during the 1997-1999 period. Twenty six taxon belonging to the subfamilies Tanypodinae and Chironomini were identified. Taxonomic diversity decreased with increasing depth in the lake, but the occurrence of Chironomidae larvae was noted even in the deepest part of the lake. Chironomidae clearly indicated that Lake Łękuk Wielki is recovering.

We sampled macroinvertebrate assemblages in the littoral benthos and on the surface of snags in the Upper Mississippi, Missouri, and Ohio rivers. Snag assemblages differed from benthic assemblages. Tubificids, Caenis, Tanytarsus, Cryptochironomus, Limnodrilus, and Chironomini were consistently more abundant in the benthos; Nais, Cricotopus/Orthocladius, Nematoda, and Rheotanytarsus were consistently more abundant on snags. Filterers were more abundant and gatherers were less abundant on snags than in the benthos. Snag assemblages differed among rivers and among reaches within rivers. Variation among reaches was the result of direct and indirect effects of high-dam reservoir impoundments (upper vs lower Missouri River) and low-dam impoundment for navigation (impounded vs free-flowing Upper Mississippi River). The maximum relative abundance of filterers in the lower Missouri River, which was the only long unregulated reach we studied, was related to particulate organic C and sestonic chlorophyll a c...

Summary Vibrio cholerae is a natural inhabitant of aquatic ecosystems, yet its interactions within this habitat are poorly understood. Here we describe the current knowledge on the interaction of V. cholerae with one group of co-inhabitants, the chironomids. Chironomids, non-biting midges (Chironomidae, Diptera), are an abundant macroinvertebrate group encountered in freshwater aquatic habitats. As holometabolous insects, chironomids start life when their larvae hatch from eggs laid at the water/air interface; through various feeding strategies, the larvae grow and pupate to become short-lived, non-feeding, adult flying insects. The discovery of the connection between V. cholerae and chironomids was accidental. While working with Chironomus transavaalensis, we observed the disintegration of its egg masses and searched for a possible microbial agent. We identified V. cholerae as the primary cause of this phenomenon. Haemagglutinin/protease, a secreted extracellular enzyme, degraded the gelatinous matrix surrounding the eggs, enabling bacterial growth. Observation of chironomids in relation to V. cholerae continuously for 7 years in various types of water bodies in Israel, India, and Africa revealed that environmental V. cholerae adhere to egg-mass surfaces of various Chironomini (‘bloodworms’). The flying adults' potential to serve as mechanical vectors of V. cholerae from one water body to another was established. This, in turn, suggested that these insects play a role in the ecology of V. cholerae and possibly take part in the dissemination of the pathogenic serogroups during, and especially between, epidemics.

We analysed the distribution of living larval Chironomidae (Insecta: Diptera) along a depth transect (0–80 m water depth) at Kigoma Bay in Lake Tanganyika (East Africa) to explore the ecological indicator value of Lake Tanganyika's midge fauna and to delineate the habitat preferences of resident larvae. Additionally, by comparing the taxonomic resolution reached in live versus fossil chironomid studies in this lake, we appraised the general information content of African fossil chironomid assemblages and, therefore, the quality of African chironomid-based palaeoenvironmental reconstructions. We found 141 chironomid specimens, representing two Tanypodinae, one Orthocladinae and 13 Chironominae (seven Chironomini and six Tanytarsini) taxa. All of these are conspecific to larval types encountered in subfossil collections from Lake Tanganyika or smaller East African lakes, but their differential diagnoses are updated here to include exoskeletal elements that are generally better preserved on live specimens. T...

Xylochironomus kakadu, a new genus and species of wood-mining chironomid, is described from northern Australia. Formerly known by a code 'unknown genus K1', the larvae mine soft immersed timber in tropical Australia. The basal striae on the larval mandible are observed otherwise only in Chironomus Meigen and likely close relatives currently placed in Einfeldia Kieffer. The adult male could key as a tanytarsine, and all stages superficially resemble Polypedilum Kieffer, except for the bare squama and the non-tapered male tergite VIII, and the dorsal larval head sclerites. However, analyses of a morphological data matrix derived from all life history stages support no such relation- ships. Instead, a relationship to Paralauterborniella Lenz and Apedilum Townes, and at one remove, to Fissimentum Cranston & Nolte and Imparipecten Kieffer is postulated. Larval wood-mining among the early branching Chironomini is evidently frequent, but taxa appear not to form a monophyletic clade.

Chironomid midges are abundant and important components of freshwater communities, but estimating their production is problematic because of taxonomic difficulties, short generation times, and overlapping cohorts. We measured growth rates of nontanypodine chironomid larvae from a 3rd-order stream in southern Illinois, USA, at different temperatures to estimate assemblage-level production using the instantaneous growth method. We collected Chironomini, Tanytarsini, and Orthocladiinae larvae, separated them into small (0–3.9 mm), medium (4–7.9 mm), and large (8–12 mm) size classes, and then reared larvae in a controlled environment for 3 to 7 d at temperatures ranging from 5 to 28°C. We measured lengths of individual larvae before and after each trial and estimated biomass using a length–mass regression. Instantaneous growth rates (g) across all size classes ranged from 0.008 mg mg−1 d−1 at 5°C to 0.24 mg mg−1 d−1 at 22°C. Instantaneous growth rates of small larvae increased linearly with temperatur...