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A long-term study of adult non-biting midges (Chironomidae) active in winter on the snow in mountain areas and lowlands in Poland yielded 35 species. The lowland and mountain communities differed significantly in their specific composition. The mountain assemblage was found to be more diverse and abundant, with a substantial contribution from the subfamily Diamesinae, whereas Orthocladiinae predominated in the lowlands. Orthocladius wetterensis Brundin was the most characteristic and superdominant species in the winter-active chironomid communities in both areas. Only a few specimens and species of snow-active chironomids were recorded in late autumn and early winter. The abundance of chironomids peaked in late February in the mountain and lowland areas with an additional peak in the mountain areas in early April. However, this second peak of activity consisted mainly of Orthocladiinae, as Diamesinae emerged earliest in the season. Most snow-active species emerged in mid- and late winter, but their seasonal patterns differed between the 2 regions as a result of the different species composition and the duration of snow cover in these regions. Spearman's rank correlation coefficient tests yielded positive results between each season and the number of chironomid individuals recorded in the mountain area. A positive correlation between air temperature, rising to +3.5 °C, and the number of specimens recorded on the snow in the mountain community was statistically significant. The winter emergence and mate-searching strategies of chironomids are discussed in the light of global warming, and a brief compilation of most important published data on the phenomena studied is provided.

Emergence of Diamesa cheimatophila was determined for a five year period (1981–1986) using a permanently operated walk-in emergence trap over a spring-fed tributary of Fourmile Creek in Erie, northeast Pennsylvania. Annual emergence started in September/October, continued sporadically through winter until April/May and occurred over a span of 185–236 days. Averaged over the five years of our study, > 80% of annual emergence occurred during winter when long-term average air temperatures are less than 10 degrees C. Emergence of D. cheimatophila shows patterns similar to emergence of D. mendotae Muttkowski at groundwater-influenced stream sites in Minnesota, where it is known to produce 2–3 cohorts per year during winter. Well-defined peaks in winter emergence of D. cheimatophila indicates at least two, but possibly three or four cohorts emerging per winter. The year-to-year variability in emergence of D. cheimatophila strongly suggests this species also conforms to the Labile Life Cycle Hypothesis proposed for D. mendotae, (but refined in this paper) with the actual number of cohorts produced per winter depending on the onset and duration of cold air temperatures.

Resistance to desiccation in larvae of eight species of aquatic, semiaquatic and terrestrial chironomids (Pseudodiamesa branickii, Macropelopia sp., Prodiamesa olivacea, Micropsectra sp., Chironomus riparius, Chironomus dorsalis, Metriocnemus martini and Camptocladius stercorarius) was studied. The larvae were desiccated in exicator at constant conditions (15 °C, 80% RH) and changes in moisture and body water content was recorded. The LD-50 for loss of body water was calculated. The lowest resistance to loss of body water was found in larvae from subfamilies Tanypodinae and Diamesinae Macropelopia sp. and P. branickii. They survived loss of 49.7 and 56.6% of original water content (presented values are LD-50). On the other hand the highest resistance to water loss was found in C. dorsalis. M. martini and C. stercorarius. The larvae of these species may survive loss of 67.4, 76.6 and 84.2% of original water content. Nevertheless the survival time under experimental conditions depends more closely on larval size than on lethal level of water loss. The smaller larvae desiccated faster and perished sooner than large ones despite they tolerate higher loss of body water.

Insects inhabiting cold streams must either tolerate or avoid freezing to survive. The present study reports the strategy adopted by fourth-instar larvae of two chironomid species [Pseudodiamesa branickii (Nowicki) and Diamesa cinerella (Meigen)] overwintering in a glacial stream (in the Italian Alps). The cold adaptive potential of both species under acute cold stress is investigated down to –30 °C. Supercooling points, lower lethal temperatures (LLTs), haemolymph thermal hysteresis, whole body content of sugars and polyols, and the expression of heat shock protein (HSP) genes (hsc70 and hsp70) expression are estimated. Comparable thermal hysteresis (> 2 °C) is measured in the two species, both of which accumulate glucose and sucrose as the main cryoprotectants. According to the supercooling points (= –6.37 and –6.85 °C, respectively) and LLT100 (= –16.2 and –14.7 °C, respectively), P. branickii and D. cinerella can both be considered as freeze tolerant. However, the cumulative proportion of individual freezing values and the LLT50 (–9.14 and –6.13 °C, respectively) suggest that P. branickii is more cold hardy than D. cinerella, whereas the gene expression data (i.e. an absence of up-regulation of hsp70 in D. cinerella) suggest that D. cinerella is more cold hardy than P. branickii. These findings are discussed in relation to the validity of the different metabolic indicators for defining the level of cold hardiness of a species, even in relation to its cold stenothermy. The results are also discussed in relation to climate warming, which represents a serious threat for species from glacier-fed streams.

A new tribe of Diamesinae, Eugenodiamesini tr. nov. (Diptera: Chironomidae), is described based on a single pupa from Khutel Khara (lower part of the Tsagan Tsab Formation, Lower Cretaceous of Mongolia). The most distinctive characters of the new taxon are numerous multibranched lateral setae on tubercles along entire margins of abdominal segments II–VIII, and a unique setation of the anal lobes, with two multibranched anal macrosetae on each side and one simple near the apex. The fossil is the oldest known member of Diamesinae.

Rapidly declining diversity of freshwater species necessitates surveys to document and describe patterns in biodiversity. To this end, a survey of Chironomidae (Insecta: Diptera) was conducted in a remote watershed of western Alaska. Larval chironomids were collected from 16 stream sites in the Kuskokwim River watershed in 2009 and 2010. Twenty-seven chironomid taxa were identified. Orthocladiinae was the most diverse subfamily and was numerically dominant at all sites except a glacial runoff stream where Diamesinae was numerically dominant. Two rare chironomids were collected in the study: an undescribed species of Stilocladius and a species of Orthocladius (Mesorthocladius). The latter genus has only 2 described species in North America, one in Ohio and one in Minnesota. Results of a nonmetric multidimensional scaling analysis indicated that sites varied based on changes in elevation, conductivity, pH, and percent Diamesinae. Two high-elevation sites, one at the outflow of a lake and the other...

Karyotypes and characteristic features of the polytene chromosomes are described for 55 species of the subfamilies Tanypodinae, Diamesinae, and Prodiamesinae; this is almost 3 times as many species as were included in the previous reviews published in the 1980s.

In order to determine the Chironomidae and Chaoboridae fauna of Kartal Lake, Karagöl and Gökçeova Pond, samplings were performed in the summer months of 2009-2011. Benthic samples were collected from the littoral and profundal zones of the water bodies by using 180 µ mesh sized hand nets and Ekman Birge grab, respectively. As a result of the taxonomic study, totally 27 species were determined; of them 26 belong to five submailies (Tanypodinae, Prodiamesinae, Diamesinae, Orthocladiinae, Chironominae) of Chironomidae and one to Chaoboridae. The Chironominae subfamily was the dominant group with 16 taxa and was followed by Tanypodinae with 5 taxa. All the determined taxa were firstly recorded from the studied localities. This study aims to add a new one to our country’s mountain lakes studies and to determine common specimens which are unique for this environment characteristics.Keywords: Chironomidae, Chaoboridae, benthos, mountain lakes, Denizli ilinde yer alan Kartal Gölü, Saklıgöl, Karagöl ve Gökçeova Göleti’nin Chironomidae ve Chaoboridae faunasının tespiti amacıyla 2009-2011 yılları yaz mevsimlerinde örnekleme çalışmaları yapılmıştır. Bentik örnekler her gölün litoral ve profundal bölgelerinden 180 µ göz açıklığındaki el kepçeleri ve Ekman-Birge grab ile toplanmıştır. Taksonomik çalışma sonucunda, Chironomidae familyasının 5 altfamilyasına (Tanypodinae, Prodiamesinae, Diamesinae, Orthocladiinae, Chironominae) ait 26, Chaoboridae familyasına ait 1 olmak üzere toplam 27 takson saptanmıştır. Chironominae 16 taksonla baskın olup bu alt familyayı 5 taksonla Tanypodinae izlemektedir. Tespit edilen taksonlar çalışılan lokaliteler için yeni kayıttır. Bu çalışmanın amacı, ülkemizin dağ gölleri ile ilgili çalışmalarına hem bir yenisini daha eklemek hem de kendine özgü bir ortam teşkil eden bu habitatların karakteristik olan ortak türlerini çıkarmaya çalışmaktır

Some rare species from Italian Alps, belonging to the genus Diamesa Meigen, 1835 (Diptera, Chironomidae) are here redescribed as adult males, because only old, incomplete descriptions are available for these taxa. Terminology of male genitalia is reviewed, diagnostic features are illustrated in detail, and notes on biology and geographical distribution of the examined species are provided. An identification key to the known adult males is presented.

An annotated list of chironomid species is presented for the watercourses and waterbodies of the Kama River Basin, which covers the territories of Perm krai, Sverdlov oblast’, Kirov oblast’, the Udmurt Republic, and the Republic of Bashkortostan. The list includes 253 species of 107 genera and 6 subfamilies: Podonominae (2 species), Tanypodinae (35), Diamesinae (10), Prodiamesinae (4), Orthocladiinae (92), and Chironominae (110). Eighty one of these species were defined under the imagoes.

Macroinvertebrate drift was sampled at 15 sites along the Tongariro River, New Zealand above and below two hydroelectric dams. Sixty-seven invertebrate taxa were collected in the drift. Trichoptera (31) were the most diverse, followed by Diptera (13), Ephemeroptera (8) and Plecoptera (8). However, chironomidae were the numerically dominant taxa in the drift throughout the river and represented over 80% of all animals collected. Of these, Orthocladiinae and Diamesinae were the most abundant. Taxonomic richness declined with distance downstream and peaked at sites with intermediate levels of periphyton biomass. The per cent of Ephemeroptera, Plecoptera and Trichoptera (EPT) was 3–4 times higher in the unregulated section of the river and declined exponentially with both distance downstream and increase in periphyton biomass, but densities were similar along the river. Of the measured environmental variables periphyton biomass was most closely linked with drift community structure. Periphyton biomass was six times higher in the lower section of the river than the upper unregulated section. The autocorrelation between periphyton biomass and distance downstream complicates the interpretation of results. However, because of the distinct differences between above and below dam sections of river in periphyton biomass and the strong link between it and invertebrate drift we suggest that the alteration of flow patterns by the hydroelectric dams and the associated shift in periphyton biomass is the most likely explanation for invertebrate drift patterns in the river. Copyright © 2009 John Wiley & Sons, Ltd.

SUMMARY 1. The ecology of glacier-fed streams at temperate latitudes has been intensely studied in recent years, leading to the development of a well-validated conceptual model on the longitudinal distribution of macroinvertebrate communities downstream of the glacier margin (Freshwater Biology, 2001a; 46, 1833). However, to our knowledge, the ecology of tropical glacier-fed streams has not yet been studied. 2. We sampled benthic macroinvertebrates and measured environmental variables at nine sites between 4730 and 4225 m altitude along a 4.3 km stretch of a glacier-fed stream 40 km south of the equator in the Ecuadorian Andes. Our goal was to study the longitudinal distribution of the fauna in relation to environmental factors and to compare this with the conceptual model based on temperate–arctic glacier-fed streams. 3. Total density of invertebrates differed considerably at the two highest altitude sites; 4600 m )2 at a pro-glacial lake outlet and only 4 m )2 at a site originating directly from the glacier snout. Otherwise, there was a downstream decrease in density to about 825 m )2 at the three lowest sites. Taxon richness increased with distance from the glacier, very similar to the pattern predicted. A total of 28 taxa were collected; two at the glacier snout, seven at the nearby pro-glacial lake outlet, 13 at site 2 (

An annotated list of chironomid species from some waterbodies and watercourses of Mongolia identified by an imaginal developmental stage is presented. The list includes 97 species of 39 genera and 5 subfamilies: Tanypodinae (6 species), Diamesinae (1), Prodiamesinae (2), Orthocladiinae (33), and Chironominae (55). Of all found chironomid imagos, 11 species have been earlier identified for the Mongolian fauna, the other 86 species have been registered for the first time. The largest number of species has been recorded in Lake Sangiyn-Dalai—28; in Lake Ugiy and River Ider—19 species. In the rest of the lakes, the number of recorded species varies from 18 to 10 species, and in rivers, from 13 to 2. Most of the species are boreal and widespread. The number of Paleoarctic species amounts to 44 and Holarctic species amounts to 49.

An annotated list of chironomids (33 species) and blackflies (23 species), identified mainly by their preimaginal phases, is given for the Hrazdan River, Armenia. The list of chironomids comprises five subfamilies: Tanypodinae (1 genus), Diamesinae (1), Prodiamesinae (1), Orthocladiinae (14), and Chironominae (4). The hydrochemical investigation of the Hrazdan River performed in 2002–2004 showed the water quality to vary between years, seasons, and places.

Due to their sensitivity, remote mountain lakes and streams are not only vulnerable to environmental change but also excellent sensors of such changes. Notwithstanding their importance as an ultimate resource of unpolluted waters, the alpine biome remains one of the less studied ecosystems in the world. This study involved the analysis of a database of zoobenthic communities collected in 36 inlets and 44 outlets of Swiss (Canton Bern) and Italian (Piedmont, Trentino-Alto Adige) Alpine lakes. All the streams are above the tree line and were sampled qualitatively in September/October (mostly in 2000) by disturbing the substrate and concentrating the dislodged animals with a standard pond net (250 μm mesh size). Generally higher population densities and taxon richness were found in the outlets than in the inlets. Fifty-seven per cent of taxa were common to the two stream types, with 17% found exclusively in the inlets and 26% in the outlets. Piedmont had the highest number of taxa found only in the region, Trentino-Alto Adige the lowest number. Insects represented 89% and 81% of the zoobenthic community of inlets and outlets, respectively. Among the insects, Diptera prevailed, with Chironomidae accounting for 68% of the mean inlet communities and 45% of those found in the outlets. The subfamily of Diamesinae was far more abundant in the inlets (16%) than in the outlets (1%). In contrast, the outlets hosted more Ephemeroptera, Trichoptera, Plecoptera, Oligochaeta and Tricladida. Some significant differences regarding the distribution of some species were found along the West–East and South–North gradients. The lakes appeared to affect the structure of the stream zoobenthic community by ameliorating the harsh physico-chemical conditions of the tributaries but no evidence was found indicating an increase in organic matter. In fact, filter-feeding invertebrates did not show any significant increase in the outlets, though the number of these taxa was higher downstream of the lakes.

Deformities in the mouthparts of larval Chironomidae, particularly of the teeth on the mentum, have been proposed as a bioindicator of sediment quality and environmental stress. Most work to date has concentrated on relatively few abundant, responsive genera common in soft-bottom lakes. We examined mentum deformities in 25 genera of Chironominae, Orthocladiinae and Diamesinae (one genus) from streams and a lake in rural Nova Scotia where farming and forestry are the principal land uses. Incidence of deformity at similar stream sites varied across genera from zero to >10%. Average frequencies of deformity across all three subfamilies at sites with no known sources of contamination ranged from

The relative influence of water regime and other environmental factors on the organization of benthic macroinvertebrates was studied over three years in a small intermittent river basin (River Pula) in Sardinia. The intermittent nature of the led to high spatial and temporal variability of abiotic characteristics. Twenty-eight invertebrate taxa accounted for 90% of the sampled individuals; and of there four (Chironominae, Caenis luctuosa, Diamesinae, Protonemura ichnusae) accounted for more than 50% of the total density. Canonical correspondence analysis showed that 34.6% of the biological variance was accounted for by abiotic factors and that different environmental features, including sediment structure and stream order, had a larger influence on benthic macroinvertebrate distribution and abundance than the intermittent water regime, even though local drought events completely disrupted the macroinvertebrate community.

Data on the species composition, abundance, and biomass of macrozoobenthos in the rapids of a small river flowing in the foothills of the southwestern Kamchatka Peninsula are considered along with the results of quantitative analysis of structural rearrangements in the lithophilic community under the effects of changes in the granulometric composition of bottom sediments. Groups of lithophilic and pelophilic invertebrates typical of the metarithral of such rivers (e.g., chironomids of subfamilies Diamesinae and Prodiamesinae) are identified.

Chironomid communities from three glacial and three non-glacial high mountain streams in three Alpine river basins were analyzed (Conca, Niscli, Cornisello, NE Italy, 46° N, 10° E). Eighteen sampling reaches belonging to five stream types (kryal, subkryal, glacio-rhithral, kreno-rhithral, outlet) were investigated. At each reach, geomorphological, physical, chemical and biological data were collected. Field surveys were carried out during three periods per year from 1996 to 1998: immediately after spring snowmelt, in mid-summer and in early autumn. In all, 439 zoobenthos samples were collected from 5 to 10 microhabitats of 0.1 m2 in each reach and date using a standard pond net (mesh size of 250 μm). About 50% of individuals collected were chironomids (26 673 specimens, 53 taxa), with densities ranging from 4 to 2652 ind m−2. With few exceptions, they dominated as number of taxa and individuals in all reaches. Chironomid subfamilies Diamesinae and Orthocladiinae were most abundant, especially in glacial reaches, where Diamesa spp. constituted up to 100% of the total fauna. Chironomid distribution was analyzed in relation to 37 abiotic variables, referring to stream origin, hydrology, geomorphology, physics and chemistry. Diamesa steinboecki, D. latitarsis gr. A and Pseudokiefferiella parva were the taxa best associated with ‘glacial’ conditions (i.e. high channel instability or presence of bedrock, high suspended solids and total phosphorous content, low conductivity and silica content, highly variable diel discharge and low mean temperature), while Pseudodiamesa branickii, Corynoneura spp., Eukiefferiella spp., Parorthocladius nudipennis, Tvetenia calvescens/bavarica, Thienemaniella spp. and Micropsectra atrofasciata were mostly associated with ‘non-glacial’ conditions. Substratum particle size, water depth, current velocity, the presence of riffles/pools and of mosses/algae (Hydrurus foetidus) were the major factors affecting microdistribution of chironomids in the investigated streams.

A new species, Pagastia hidakamontana sp. nov., is described from the alpine zone of the Hidaka Mountains in Hokkaido, Japan. Pagastia orthogonia Oliver, so far known only from the Nearctic Region, is newly recorded from Japan and redescribed. Females of P. lanceolata (Tokunaga) and P. nivis (Tokunaga) are redescribed, and the synonymy of P. lanceolata with Syndiamesa (Lasiodiamesa) crassipilosa Tokunaga (= Pseudodiamesa crassipilosa) is proposed. Keys to males and females of Japanese species of the genus are provided.

A field experiment was conducted using ceramic plates as experimental substrates to describe the colonizing pattern of a stream invertebrate community after disturbance, and to ascertain the importance of colonizing ability for succession in a Japanese stream. We employed the simultaneous removal design in which plates were periodically set in place (1, 2, 4, 8, 16 and 32 days before sampling) and all plates were sampled on the last day of the experiment, to diminish the influence of seasonal change in stream invertebrates. Total abundance and taxon richness reached a plateau after 4‐ 16 days of colonization. In contrast, the relative abundance of six common taxa and community structure changed throughout the 32 days of colonization. Differences in the colonizing ability of the stream invertebrates were evident. Taxa with high mobility, such as the mayflies Baetis thermicus , Paraleptophlebia japonica , Cinygmula sp. and Drunella sachalinensis , colonized faster than those with low mobility (e.g. the caddisfly species Brachycentrus americanus and the chironomid midge Diamesinae spp.). The abundance of the most common taxon, Baetis , decreased at late stages of colonization, possibly because of low periphyton biomass. Consequently, we concluded that a difference in colonization ability among taxa is an important factor causing succession in stream invertebrate communities in local habitats.

Using cluster analysis, ecological profiles of the species, and the (Diamesinae + Orthocladiinae) / Chironominae ratios, prealpine rivers were classified by their chironomid communities based on 338 species: (1) summer-cold mountain rivers (Isar, Salzach, Inn/Muhldorf), (2) summer-warm moraine-stretches (Wurm, Alz/moraine rupture, Amper, Altmuhl), (3) the summer-warm lowland river Upper Alz (lake outlet and the stretch to Altenmarkt village), (4) the lower section of the river Inn regulated by dams, which is dominated by a littoral community. The river Upper Alz is faunistically differentiated along it's course. Classification of river stretches is predominantly explained by rhithral and eurytope species. Potamal and littoral species had no effect on classification. The results suggest that water temperature is the most important factor of the chironomid-based river classification, which is in harmony with studies by Rossaro (1992) and Lindegaard & Brodersen (1995). Locally, other morphological parameters as reach slope and substrate may be important factors as well. However, further data are needed to clarify their role in species distribution.

Natural and near-natural streams are rare in the densely populated areas of the Alps. A variety of anthropogenic impacts have resulted in the alteration and sometimes even complete destruction of these systems. Nowadays it is difficult to find un-impacted streams that are strongly needed to define the natural variability and ecosystem processes. The results from freshwater inventories and habitat assessments conducted in protected areas in Austria (Nationalpark Hohe Tauern) and Italy (Naturpark Rieserferner-Ahrn) were used to develop a comprehensive typology of Alpine streams. Three different levels were used to discriminate between the distinct stream/river types: source (glacial vs. non-glacial), hierarchy (i.e. location within the stream system) and topography/ channel morphology. Important characters defining the structure and function of these stream types are gradient, substrate composition, flow pattern and riparian vegetation. Benthic fauna assemblages from 99 near-natural stream segments in glacial and non-glacial systems demonstrated the effect of glaciation on abundance levels of the total macroinvertebrate fauna, EPT taxa (Ephemeroptera, Plecoptera and Trichoptera) and the chironomid subfamily Diamesinae in different altitudes. A general decrease of abundances with increasing altitude was found. While stream segments with a degree of glaciation >10% primarily showed reduced abundances at all altitudes, lower (

Chironomid head capsules from surface sediments in Kamchatka reflect a rich and diverse fauna. We observed a relatively high abundance of head capsules from the subfamily Diamesinae. An unknown morphotype of Tanytarsini, 'Tanytarsini type klein', was found in the lake sediments of two lakes from Central and southern Kamchatka.

The first data on the chironomids fauna of the Franz Josef Land archipelago belong to M. Goetghebuer (1933). He noted 16 adults males Hydrobaenus conformis (Holmgren, 1869). In the present study, three new species (Diamesa (Diamesa) arctica (Boheman, 1865), Limnophyes pumilio (Holmgren, 1869), Tokunagaia rectangularis (Goetghebuer, 1940)) and one new subfamily (Diamesinae) are recorded in the Franz Josef Land archipelago bringing the chironomid fauna in this archipelago to a total of seven species from two subfamilies.

1. Environmental variables, benthic algal biomass and macroinvertebrate fauna were examined from September 1999 to January 2000 (austral summer) along two glacier-fed rivers in South Island, New Zealand. 2. The rivers were characterized by high flow variability, high turbidity and physically disturbed beds. Water temperature ranged from

1. Benthic macroinvertebrate distribution was examined in relation to channel characteristics (including stability), substratum, hydraulic variables, primary production (chlorophylla) and coarse particular organic matter (CPOM) in an alpine glacial stream, the Mutt (Upper Rhone valley, Switzerland). Co-inertia analysis and canonical correspondence analysis were used to identify the major environmental gradients in¯uencing community variations. 2. The Mutt (length: 3.6 km, altitudinal range: 1800±3099 m a.s.l.) exhibited typical characteristics of a kryal stream. Average summer temperature remained below 2 °C immediately downstream from the snout but was on average 5 °C higher 1700 m downstream. Seasonal variations in water sources were evidenced by the high latesummer(September) contribution of groundwater with increased conductivity. 3. Sixty-six taxa were recorded from the five reaches sampled at three periods (snowmelt,ice melt and low water in late summer) in 1996 and 1997, of which 29 were Chironomidae. Three taxa of Diamesinae were the first colonizers of the stream below the glacier, but 16 taxa, including Ephemeroptera, Plecoptera and Trichoptera, were already recorded 200 m downstream. Water depth, channel slope and Pfankuch's Index of channel stability were strongly correlated with the longitudinal faunal gradient. Maximum temperature, current velocity and water conductivity were also correlated, but to a lesser extent. 4. The rapid incorporation of non-chironomid taxa into the stream community represented a departure from Milner & Petts's (1994) conceptual model of invertebrate succession downstream of glacial margins. The results confirmed that glacial stream communities are primarily driven by physical determinants.

1. A study on glacial stream ecosystems was carried out in six regions across Europe, from Svalbard to the French Pyrenees. The main aim was to test the validity of the conceptual model of Milner & Petts (1994) with regard to the zonation of chironomids of glacier-fed rivers along altitudinal and latitudinal gradient. 2. Channel stability varied considerably, both on the latitudinal and altitudinal scale, being lowest in the northern regions (Svalbard, Iceland and Norway) and the Swiss Alps. Water temperature at the upstream sites was always

1. The longitudinal distribution of macroinvertebrates was investigated in June, August and September 1996 and 1997 in the Conca glacial stream and its tributary (Italian Alps; 46°N, 10°E). The principal aim was to test the Milner & Petts (1994) model that predicts the succession of faunal groups downstream of the glacial snout in relation to water temperature and channel stability. The effect of a non-glacial tributary on the taxonomic richness and density patterns occurring in the glacial stream was also considered. 2. Channel stability showed an atypical longitudinal trend in the Conca glacial stream, being high in the upper part with Pfankuch Index values between 30 and 33. Water temperature exceeded 6 °C at all stations, with average values below 2 °C occurring only within 700 m from the glacial snout. 3. Taxonomic richness and diversity increased downstream. Taxonomic richness in the glacial stream (at about 1.5 km from the glacier) was comparable with the tributary and the reach after the confluence. Abundance also increased downstream in the glacial stream, but not as greatly as the number of taxa. 4. At higher taxonomic levels, the community structure in the tributary stations appeared to be similar to the two stations in the glacial stream just upstream of the confluence. The effect of the tributary was evident mainly at the genus or species level of the Chironomidae community. Some taxa found in the non-glacial stream (e.g. Cricotopus fuscus, Eukiefferiella coerulescens, Metriocnemus sp., Paratrichocladius rufiventris, P. skirwitensis, Rheocricotopus effusus and Smittia sp.) were found also in the Conca stream but only after the confluence. 5. The upper glacial reach (within 700 m from the glacier snout) was dominated by the chironomid Diamesa spp. Less than 400 m from the glacier other Diamesinae (Pseudokiefferiella parva) and a few Orthocladiinae, especially Orthocladius (Euorthocladius) rivicola gr., colonized the stream. Some Diamesinae maintained relatively dense populations at mean water temperature around 5 °C, while some Orthocladiinae colonized reaches with mean water temperature

1. Macroinvertebrate communities in two Norwegian glacial rivers, one in the western fjords (Dalelva) and one in the eastern mountains (LeirungsaEi), were investigated during three time periods in 1996 and 1997. 2. Channel stability variables (substratum heterogeneity/Pfankuch index/hydraulic stress) and water temperature accounted for 54% of the total inertia in the principal components analysis (PCA) ordination of environmental variables. The importance of these variables was con®rmed by cluster analysis. 3. The two rivers were well separated in the ordinations, with LeirungsaE i showing much greater heterogeneity. This is explained by differences in altitudinal range, terrestrial vegetation and the importance and nature of tributary inputs. 4. Channel stability and temperature were also important in determining faunal communities in the two glacial rivers, supporting the main determining variables in the conceptual model of glacial streams (Milner & Petts, 1994). However, clear temporal differences were apparent in the data, the two rivers being more similar during the summer period of high discharge dominated by glacial meltwater. During spring and especially during autumn environmental conditions and the macroinvertebrate fauna differed both within and between rivers. 5. Diamesinae dominated in the upper reaches of both rivers, with Orthocladiinae becoming more common downstream. The dominance of Diamesinae persisted further down Dalelva because of the continued in¯uence of glacial tributaries, whereas in LeirungsaEi the in¯uence of non-glacial tributaries led to a change towards a greater proportion of Orthocladiinae. Lakes modi®ed macroinvertebrate communities in both river systems.

1. Generalized additive models (GAMs) were used to predict macroinvertebrate taxonomic richness and individual taxon diversity at the reach level across seven European glacier-fed river sites from a set of 11 environmental variables. Maximum water temperature and channel stability were found to explain the most deviance in these models. 2. Using this information, and data from other recent studies of glacier-fed rivers, a modified conceptual model based on Milner & Petts (1994) is presented which predicts the occurrence of macroinvertebrate families and subfamilies as determined by maximum water temperature (Tmax) and channel stability. This deterministic model only applies to the summer meltwater period when abiotic variables drive community structure. 3. Where maximum water temperature is below 2 °C, Diamesinae chironomids are typically the sole inhabitants, but where Tmax >2 °C but

Summary The phylogeny of the subfamilies of Chironomidae are cladistically analysed using parsimony. A data matrix is presented and some characters discussed. Different outgroup taxa, constraints and options are used, characters unordered or ordered, weighted or unweighted, the results reweighted or not and the results discussed. Telmatogetoninae in all cladograms forms the sister group of the remaining subfamilies. Aphroteniinae in some cladograms forms the sister group of all subfamilies except Telmatogetoninae, whereas in other cladograms, including the preferred cladogram, it is part of Tanypodoinae, which otherwise includes Podonominae, Usumbaromyiinae and Tanypodinae. Chilenomyiinae is basal in Tanypodoinae in some cladograms. In most cladograms, including the preferred cladogram, it is basal in Chironomoinae, which also includes Buchonomyiinae, Diamesinae, Prodiamesinae, Orthocladiinae and Chironominae. The preferred cladogram is compared with the relationships between different subfamilies suggested by previous authors.

Taxonomic composition and emergence phenologies of Chironomidae inhabiting an intermittent stream in eastern Kansas were determined over a three year period using collections of surface-floating pupal exuviae. Duration of surface flows varied substantially over the period of study, ranging from 266 days in 1993-1994 to 215 days in 1994-1995 and 137 days in 1995-1996. The stream bed dried completely during summer and/or fall in all three years. Fifty-five species emerged from the stream during the study, with Orthocladiinae having the greatest species richness (26 taxa), followed by Chironomini (14), Tanytarsini (10) and Tanypodinae (5). No Diamesinae, Prodiamesinae, Podonominae nor Pseudochironomini were present. Annual emergence varied considerably with 29 species in 1993-1994, 49 species in 1994-1995 and only 6 species in 1995-1996. During the first two years the phenological patterns resembled those expected for small, cooler-water streams, with winter and early spring emergence dominated by Orthocladiinae. The peak in emergence of Orthocladiinae was followed by a small but distinct increase in Tanytarsini in early spring, then Chironomini became more common as water temperatures increased and surface discharge declined. The timing of emergence was strongly influenced by the date at which surface discharge began, and resulted in about a 2 month shift between 1993-1994 and 1994-1995. Averaged over the three years of the study, emergence was dominated by seven species: Corynoneura sp. 1, Corynoneura sp. 2, Orthocladius lapponicus, Parametriocnemus cf. lundbecki, Thienemanniella sp., Larsia decolorata, and Zavrelimyia sinuosa. The remaining species consisted of a mixture of species common in perennial streams plus (1) winter/early spring emerging species that likely persist in the stream in desiccation-resistant stages or in the hyporheic during periods of intermittency, (2) semiaquatic or semiterrestrial species, and (3) species of genera in which larvae are known to produce cocoons and diapause, or occur in moist sediments. We estimate that as many as 60 % of the species of Chironomidae are facultative or specialist species that characterize this intermittent stream.

A new species, Diamesa amanoi sp. п., from Mera La (alt. 5,050 m), Nepal is described. The present new species is most closely related to D. subletti Makarchenko from North America. Diamesa plumicornis Tokunaga which had been regarded as Japanese endemic species is newly recorded from South Korea, and D. pankratovae Makarchenko et Bulgakov is recognized as a new synonym of D. filicauda Tokunaga.

The Wiederholm 1983 key to the larvae of the Holarctic Chironomidae was by far the most used book during my PhD and my post-doctoral years. It shaped my understanding of chironomid classification and identification, and provided the basis for most of my work as a chironomid ecologist and palaeoecologist. It is, therefore, with high expectations (will there be new taxa?) and some dread (will I have to rethink my classification?) that I opened the copy of the revised “Chironomidae of the Holarctic region. Key and diagnoses Larvae” that was kindly provided to me by Lennart Cederholm at Scandinavian Entomology Ltd. At first glance, the book, edited by Trond Andersen, Pete Cranston, and John Epler, does not look much different than the original edited by Torgny Wiederholm. It has the same cover, color, and is similarly massive, although the format has changed the book has now become several centimeters broader. My first impression was one of slight disappointment. Many of the figures are obviously identical as in the 1983 version, but not as well reproduced. In many sections the text also remains more or less the same, especially in the larval descriptions for the different genera. The chapters are presented in a similar order, starting with an introduction and a section describing the morphology of the larvae, followed by a key to the different subfamilies. These initial chapters are followed by sections dealing with the different subfamilies: Buchonomyiinae, Podonominae, Tanypodinae, Telmatogetoninae, Diamesinae, Prodiamesinae, Orthocladiinae, and Chironominae. The book also includes a foreword and an index of the discussed Holarctic chironomid taxa.

The subfamily Prodiamesinae is closely related to the Diamesinae and Orthocladiinae. In Europe, the subfamily contains only four genera: Monodiamesa, Odontomesa, Prodiamesa and Propsilocerus. This chapter describes the systematics, biology and ecology of genera and species of the Prodiamesinae. Details such as the distribution in Europe and the Netherlands, feeding habits, microhabitat information, and the type of water dwelling, are briefly outlined for Monodiamesa bathyphila, Odontomesa fulva, Prodiamesa olivacea, Prodiamesa rufovittata and Propsilocerus lacustris. Odontomesa fulva is the only species of the Odontomesa genus in Europe. Four Prodiamesa species have been described in Europe, two of which occur in the Netherlands and adjacent lowlands. In the Netherlands Prodiamesa olivacea is widely distributed in the Pleistocene area, in southern Limburg and in the dune region. Propsiloceru lacustris has been recorded in eastern and central Europe, westward to northern Germany. There are no recent records from the Netherlands.Keywords: Diamesinae; Monodiamesa bathypila; Netherlands; Odontomesa fulva; Orthocladiinae; Prodiamesa olivacea; Prodiamesinae; Propsiloceru lacustris

Lappodiamesa multiseta sp.n., Arctodiamesa sp. from the Russian Far East and Arctodiamesa breviramosa sp.n. from the arctic region of East Siberia are described. These species differ from related species in characteristics of the male adult, the pupa and the larva. A key to the Holarctic species of Lappodiamesa Serra‐Tosio is given.

Rapid and efficient DNA-based tools are recommended for the evaluation of the insect biodiversity of high-altitude streams. In the present study, focused principally on larvae of the genus Diamesa Meigen 1835 (Diptera: Chironomidae), the congruence between morphological/ molecular delimitation of species as well as performances in taxonomic assignments were evaluated. A fragment of the mitochondrial cox1 gene was obtained from 112 larvae, pupae and adults (Diamesinae, Orthocladiinae and Tanypodinae) that were collected in different mountain regions of the Alps and Apennines. On the basis of morphological characters 102 specimens were attributed to 16 species, and the remaining ten specimens were identified to the genus level. Molecular species delimitation was performed using: i) distance-based Automatic Barcode Gap Discovery (ABGD), with no a priori assumptions on species identification; and ii) coalescent tree-based approaches as the Generalized Mixed Yule Coalescent model, its Bayesian implementation and Bayesian Poisson Tree Processes. The ABGD analysis, estimating an optimal intra/interspecific nucleotide distance threshold of 0.7%-1.4%, identified 23 putative species; the tree-based approaches, identified between 25–26 entities, provided nearly identical results. All species belonging to zernyi, steinboecki, latitarsis, bertrami, dampfi and incallida groups, as well as outgroup species, are recovered as separate entities, perfectly matching the identified morphospecies. In contrast, within the cinerella group, cases of discrepancy arose: i) the two morphologically separate species D. cinerella and D. tonsa are neither monophyletic nor diagnosable exhibiting low values of between-taxa nucleotide mean divergence (0.94%); ii) few cases of larvae morphological misidentification were observed. Head capsule color is confirmed to be a valid character able to discriminate larvae of D. zernyi, D. tonsa and D. cinerella, but it is here better defined as a color gradient between the setae submenti and genal setae. DNA barcodes performances were high: average accuracy was ~89% and precision of ~99%. On the basis of the present data, we can thus conclude that molecular identification represents a promising tool that could be effectively adopted in evaluating biodiversity of high-altitude streams. PLOS ONE

Flow preferences of five major chironomid taxa (Cricotopus, Orthocladiinae sp. a, Eukiefferiella, Tanytarsus vespertinus, and Maoridiamesa) were investigated in December 1990 at three sites in Tongariro River, central North Island, New Zealand. Exponential polynomial preference curves indicated that most taxa were found predominantly in water ≤ 0.5 m deep when data from all sites were combined (range of conditions sampled = 0.1–1.5 m). Cricotopus and Orthocladiinae sp. a appeared to have broad velocity preferences over the range sampled (0.1–1.8 m s−1 ). In contrast, T. vespertinus had a velocity optimum of 0.1 m s−1, and Maoridiamesa had an optimum > 1.0 m s−1 at all sites. Abundances of Eukiefferiella were greatest over an intermediate range of velocity conditions (0.7–1.5 m s−1 ). Mechanisms leading to differences in velocity optima amongst chironomid taxa may include differential oxygen requirements, and changes in food supply. When determining optimal minimum flows for benthic chironomid com...

After the formation of a drinking water reservoir at Butoniga, Istria, research on the fauna of the Chironomidae larvae was undertaken in the feeder waters and the reservoir itself. Forty eight species were identified, belonging to the subfamilies Chironominae, Orthocladiinae, Diamesinae and Tanypodinae. Chironomidae colonized the reservoir waters relatively more quickly than other groups of macroscopic invertebrates. The similarity quotient (QS) of Chironomidae of the feeder waters and the reservoir is only 37.8%, which points to the formation of new communities in the reservoir. There were qualitative and quantitative changes in the composition of Chironomidae fauna in the river Mirna and in the river Butoniga downstream from the dam after water was released from the reservoir for the purpose of testing the dam. The Chironomid composition of the feeder waters places them in quality grade II. In the Butoniga reservoir the bottom water was assigned to grade II–III, because of the decomposition of the remains of surface fauna.

Biweekly benthic samples were collected for 1 yr in a third-order midwestern U.S. stream to determine chironomid life histories and growth patterns for the 14 numerically dominant taxa. Benthic densities during the year ranged from 7,500/m2 in October to 90,000/m2 in May. Seasonally, densities were highest in spring (49,600/m2) and lowest in summer (15,100/m2). Most Orthocladiinae and Diamesinae had multivoltine life cycles, whereas all Chironominae had either univoltine or asynchronous patterns. Low summer water temperatures, due to groundwater input, may explain how cold-adapted Diamesinae could complete more than one generation per year. Larval growth patterns (mean individual biomass versus time) of all 25 cohorts could be classified into four types of growth curves. Overall, biomass accumulation of third and fourth instars accounted for 95–99% of the maximal larval biomass. Nine cohorts had maximal growth rates during spring and autumn, whereas six cohorts had maximal growth during winter. Despite low water temperatures, the increased availability of high-quality autochthonous food resources during winter and spring may account for high growth rates during these two seasons. Combining growth and development data for all cohorts revealed an annual pattern of continuous species replacements and sequential periods of maximal growth. The recognition of these patterns is valuable in understanding the temporal dynamics of this diverse assemblage of stream insects.

The generation time ofP. branickii was studied using larval samples in conjunction with rearing experiments and continuous collection of egg masses across one year. This species produced three generations per year in a central German stream (280 m a.s.l., 50° 40′ N). Its generation time was variable and obviously influenced by the photoperiod to which eggs and larvulae were subjected. It is thus concluded that two ‘strains’ ofP. branickii were present in a single population, one bivoltine and the other trivoltine.

The male imago ofBoreoheptagyia phoenicia sp.n. (Diptera, Chironomidae) is described from material collected in Lebanon-Mount in the headwaters of the coastal river Awwaly.

The first description of the karyotype of four species of theDiamesinae subfamily is presented. The diploid chromosome number was found to be 8 in all the studied species. Judging from the banding pattern, the karyotypes ofPseudodiamesa (Pagastia) orientalis Tshern. andPseudodiamesa (Pagastia) lanceolata are very similar.P. lanceolata differs fromP. orientalis in the presence of two homozygous inversions, of which one involves about half of arm E, and the other located in arm D.Lappodiamesa willasseni Makar. et Kerk. andSympotthastia repentina Makar. are the first karyologically described representatives of the two genera. The karyotype ofL. willasseni has a large spherical chromosome. The karyotypes ofL. willasseni andS. repentina show a characteristic asynaptic region on the polytene chromosomes which is more prominent inS. repentina.

Development times of Diamesa incallida and its numbers of generations per vear were studied using in situ reanngs in conjunction with continuous collection of egg masses from the field The evidence suggested that the crenophilous D incallida laid eggs throughout the year and produced eight to ten generations per year, depending on water temperature (76°C to 80°C) This is the first proof for a muitivoltine Diamesinae as well as for continuous egg laying behaviour by a non–troprcal chironomid The comparatively large mature larvae (96 mm, 710 μ.g a f d weight) and the numerous generations per year indicate that D incallida is a highly productive component of crenal communities The importance of rearing chironomids over a sufficient number of generations is emphasized as a basis for the reliable interpretation of field data

The International Project Collection at the Museum of Zoology, University of Bergen, contains the holotypes of 239 species of Chironomidae, and paratypes of an additional 133 species, Table 1. More than 1750 slides with type material are housed in the collection. Most of the types belong in the subfamilies Orthocladiinae and Chironominae, but types of Usambaromyiinae, Podonominae, Tanypodinae, Buchonomyiinae, Diamesinae and Prodiamesinae are also represented.

Chironomidae represent up to 100% of the fauna of Alpine streams. Because they survive stress conditions such as extremely lowtemperature (annual mean cold and expression of stress proteins such as the 70 kDa Heat shock protein family. Fourth instar larvae of ten species of coldstenothermalchironomids (Pseudodiamesa branickii, Diamesa latitarsis, D. laticauda, D. cinerella, D. insignipes, D. zernyi, D.vaillanti, Orthocladius (O.) frigidus, O. (Euorthocladius) thienemanni and Paratrichocladius nivalis) were collected in a glacier-fedstream in NE Italy at two stations (1300 and 2600 m a.s.l.) and in two seasons (summer 2005 and spring 2006). Immunodetectionand quantification of the relative levels of Hsp70 family were performed via Western blot analysis. Significantly different levels ofHsp70 were detected among species. The highest amounts were recorded in P. nivalis and D. insignipes, the lowest in P. branickii.Within the genus Diamesa, lower levels of Hsp70 were observed in the most cold-stenothermal species than in the less coldstenothermalones. These differences may be explained by different species autoecology. The results provide information onbiochemical strategies of alpine midges to face cold temperatures under natural conditions and new insights into their possibleresponse to global warming.

Lappodiamesa willasseni sp.n. is described. It differs from related species in characteristics of the male adult. the pupa and the larva. A key to the species of Luppodiamesa Serra-Tosio is given. In contrast to previously described Diamesinae. the homologes of the large polytene chromosomes are often unpaired in few regions and they have a meandric structure. The four pairs of chromosomes include three metacentric and one acrocentric (spherical) chromosoine. A series of chromosome markers are described.