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We revise the Oriental species of Bruchomyiinae based on type and additional material, with first descriptions of the genus Alexanderia Wagner & Kvifte, gen. nov. and A. thailandensis Wagner, Rulik & Polseela, sp.nov. The genus further comprises Nemapalpus orientalis Edwards, 1928 (type species), Nemopalpus vietnamensis Quate, 1962 and Nemapalpus unicolor Edwards, 1928. Alexanderia thailandensis is described using morphology of males and females and DNA barcodes, whereas A. orientalis Edwards, 1928 comb.nov., A. unicolor Edwards 1928 comb.nov., and A. vietnamensis Quate 1962 comb. nov. are redescribed. The male and female internal genitalia in the genus are discussed in the context of sexual selection, and we suggest that the spermathecal ducts of the female and the basiphallic musculature of the male may be shaped by a male/female coevolutionary arms race.

Tonnoiriella Vaillant, 1971 was one of the genera not treated by F. Vaillant for his revision in Die Fliegen der paläartktischen Region. Here we provide a genus diagnosis, re-describe known species based mainly on type material, and provide descriptions and figures of the West-Palearctic species. New species described are T. aurasica sp. nov., T. italiae sp. nov., T. ikariae sp. nov., T. andradei sp. nov., T. rhodesica sp. nov., and T. goncalvesi sp. nov.; T. androsica Vaillant, 1978, T. orientalis Vaillant, 1978, and T. pallidipenis Vaillant, 1978 are nomina nuda; finally 21 species are known to date from Europe and North Africa. The ejaculatory apodeme (basiphallus) is asymmetric and bilobed, lobes are stacked; one or both lobes are connected with asymmetric, cross positioned (distiphallus) sclerites. Operating of the open–close mechanism of the aedeagus is explained. Information on larval ecology is provided and the systematic position of the genus is discussed.

Rising global temperatures force many species to shift their distribution ranges. However, whether or not (and how fast) such range shifts occur depends on species' dispersal capacities. In most ecological studies, dispersal-related traits (such as the wing size or wing loading in insects) are treated as fixed, species-specific characteristics, ignoring the important role of phenotypic plasticity during insect development. We tested the hypothesis that dispersal-related traits themselves vary in dependence of ambient environmental conditions (temperature regimes, discharge patterns and biotic interactions during individual development). We collected data over 8 years from a natural population of the crane fly Tipula maxima in central Germany. Using linear mixed-effect models, we analysed how phenotypic traits, phenological characteristics and population densities are affected by environmental conditions during the preceding 3, 6 and 12 months. We found a moderate (5.6%) increase in wing length per 1°C increase in mean annual temperatures during the previous year. At the same time, body weight increased by as much as 17.8% in females and 26.9% in males per 1°C, likely driven by increased habitat productivity, which resulted in a 16.4% (female) and 19.3% (male) increased wing loading. We further found a shorter, more synchronized emergence period (i.e. a narrower time frame for dispersal) with increasing temperatures. Altogether, our results suggest that dispersal abilities of T. maxima were negatively affected by elevated temperatures, and we discuss how similar patterns might affect the persistence of populations of other aquatic insects, especially stenoecious taxa with narrow distribution ranges. Our study calls for integration of information on temperature-induced phenotypic plasticity of dispersal-related traits into models forecasting range shifts in the face of climate change. Furthermore, the patterns reported here are likely to affect metapopulation dynamics of aquatic insects under climate change conditions and may contribute to the ongoing decline of insect biomass and diversity.

The male of Pintomyia (Pifanomyia) bolontikui sp. nov., from the Miocene Mexican amber deposits of Simojovel, Chiapas, is described. This is the second fossil phlebotomine sand fly described from Mexico. Morphological differences between fossil and extant species of American phlebotomine sand flies are discussed.

Climate change, land-use change, pollution and exploitation are among the main drivers of species' population trends; however, their relative importance is much debated. We used a unique collection of over 1,000 local population time series in 22 communities across terrestrial, freshwater and marine realms within central Europe to compare the impacts of long-term temperature change and other environmental drivers from 1980 onwards. To disentangle different drivers, we related species' population trends to species- and driver-specific attributes, such as temperature and habitat preference or pollution tolerance. We found a consistent impact of temperature change on the local abundances of terrestrial species. Populations of warm-dwelling species increased more than those of cold-dwelling species. In contrast, impacts of temperature change on aquatic species' abundances were variable. Effects of temperature preference were more consistent in terrestrial communities than effects of habitat preference, suggesting that the impacts of temperature change have become widespread for recent changes in abundance within many terrestrial communities of central Europe., Additionally, we appreciate the open access marine data provided by the International Council for the Exploration of the Sea. We thank the following scientists for taxonomic or technical advice: C. Brendel, T. Caprano, R. Claus, K. Desender, A. Flakus, P. R. Flakus, S. Fritz, E.-M. Gerstner, J.-P. Maelfait, E.-L. Neuschulz, S. Pauls, C. Printzen, I. Schmitt and H. Turin, and I. Bartomeus for comments on a previous version of the manuscript. R.A. was supported by the EUproject LIMNOTIP funded under the seventh European Commission Framework Programme (FP7) ERA-Net Scheme (Biodiversa, 01LC1207A) and the long-term ecological research program at the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB). R.W.B. was supported by the Scottish Government Rural and Environment Science and Analytical Services Division (RESAS) through Theme 3 of their Strategic Research Programme. S.D. acknowledges support of the German Research Foundation DFG (grant DO 1880/1-1). S.S. acknowledges the support from the FP7 project EU BON (grant no. 308454). S.K., I.Kü. and O.S. acknowledge funding thorough the Helmholtz Association’s Programme Oriented Funding, Topic ‘Land use, biodiversity, and ecosystem services: Sustaining human livelihoods’. O.S. also acknowledges the support from FP7 via the Integrated Project STEP (grant no. 244090). D.E.B. was funded by a Landes–Offensive zur Entwicklung Wissenschaftlich–ökonomischer Exzellenz (LOEWE) excellence initiative of the Hessian Ministry for Science and the Arts and the German Research Foundation (DFG: Grant no. BO 1221/23-1).

Two new fossil species of Bruchomyiinae (Diptera: Psychodidae), namely: Nemopalpus velteni Wagner, sp. n. (Burmese amber) and N. inexpectatus Wagner, sp. n. (Baltic amber), are described and figured, together with four extant species from the Neotropical Region: N. stuckenbergi Wagner, sp. n. (Chile), N. amazonensis Wagner & Stuckenberg, sp. n., N. similis Wagner & Stuckenberg, sp. n. (both Brazil) and N. cancer Wagner & Stuckenberg, sp. n. (Colombia). The terminalia of N. pilipes Tonnoir, 1922 are illustrated for the first time. Based on the shape of the male terminalia, N. stuckenbergi sp. n. is probably closely related to N. rondanica Quate & Alexander and to N. stenhygros Quate & Alexander, both of which occur in Brazil. Nemopalpus similis sp. n. (Brazil), N. pilipes Tonnoir (Paraguay), N. dampfianus Alexander (Mesoamerica) and N. capixaba Biral Dos Santos, Falqueto & Alexander (Brazil) form a distinct species-group of their own. Nemopalpus amazonensis sp. n. (Brazil) and N. rondanica Quate &...

A new species of Neotropical Psychodidae, Alepia apexalba sp. nov., is described from dry-forest tank bromeliads in Saba, Netherlands Antilles. Larvae, pupae and adults are described and figured. It is possible to relate larvae and adults because the latter were reared from pupae collected from the bromeliads (Tillandsia utriculata) that also contained larvae. Bromeliads are adapted to intercept canopy litter and throughfall water, and decaying litter is washed into and retained by the leaf bases. It is from this aquatic habitat that the larvae and pupae were collected.

The new genus and species, Phlebotoiella eoindianensis, from the Eocene Vastan amber deposits in western India is described and illustrated. This marks the first Psychodidae to be described from Vastan amber. The relationship of this new genus is discussed as well as its biogeographic implications.

Summary Land-use changes have degraded ecosystems worldwide. A particular concern for freshwater biodiversity and ecosystem function are stressors introduced by intensified agriculture. Typically several stressors affect freshwater ecosystems simultaneously. However, the combined effects of these multiple stressors on streams and rivers are still poorly understood, yet of critical importance to improve freshwater management. We investigated responses of benthic macroinvertebrates to three globally important agricultural stressors affecting streams (nutrient enrichment, fine sediment deposition and reduced current velocity), using 64 stream mesocosms (full-factorial 2 × 2 × 2 design, eight replicates of each treatment combination) established on the banks of the Breitenbach Stream (Hesse, Germany). The experiment ran for 1 month (16 days of colonisation, 14 days of manipulations), and all invertebrates in the mesocosms were collected at the end of this period. Fourteen of the 17 studied invertebrate response variables were affected by one or more stressors each. Negative effects on richness or abundance of pollution-sensitive Ephemeroptera, Plecoptera and Trichoptera (EPT) taxa were particularly common. Overall, both sediment addition and stream flow velocity reduction had pervasive and strong effects. Responses to sediment addition were mostly negative, whereas decreased current velocity reduced several EPT metrics but increased the abundances of some of the other common taxa. Nutrient enrichment had few effects, but these were consistently negative. Combined stressor effects were mainly additive, with only two interactions found in total, both between reduced velocity and nutrients (on the crustacean Gammarus spp. and ceratopogonid midges). This finding implies that multiple-stressor responses may be predicted from knowledge of single-stressor effects in this stream community (unlike the often synergistic or antagonistic responses observed elsewhere). However, further taxon-specific responses and interactions among stressors may have been obscured by limited taxonomic resolution, especially for the numerically dominant Chironomidae. Genetic approaches are required to address this limitation in the future.

Abundance prediction of aquatic insects (Ephemeroptera, Plecoptera, Trichoptera = EPT) based on environmental variables (precipitation, discharge, temperature) and abundance of the parent generation with Artificial Neural Nets (ANN) was carried out successfully. A general model for all species does not exist. Easy to understand models for individual species were restricted to stream sections with a characteristic set of variables. The amount of zero-values in the data did not affect the models. Transfer of one model to other stream sections resulted in a decrease of the determination coefficient B. Sufficient models for populations that have larvae in the stream all the year round required more information than for species with a diapause. All scaling options used decreased prediction quality. Long term mean values of variables and the deviation of actual from long term data were the best predictors, indicating a successful temporal link between seasonal variables and univoltine life cycles of most species tested. Prediction of monthly emergence in individual years was adequate with determination coefficients > 0.8 for five, and

Leaf litter is a major component in the organic matter budgets of streams worldwide. Shredding invertebrates are widely considered to be of central importance for the breakdown of allochthonous organic material in temperate-zone streams. However, various authors report an absence of this group in tropical streams. Various phenomena, including hydraulic disturbance, chemical leaf quality, and biotic control through macroconsumers, may cause variable shredder performance in streams. Our paper discusses the hypothesis that biogeographic distribution and the life-cycle strategies of the shredders are additional factors affecting the contribution of invertebrates to lotic decomposition processes. As a case study, we analyzed the type of organic matter inputs, the community of benthic invertebrate shredders, and the decomposition of temperate zone leaves (alder, Alnusglutinosa) in the Breitenbach (BRB), a temperate stream in Hesse, Germany, and in the Corrego Tenente Amaral (CTA), a neotropical Cerrado ...

Competing hypotheses that try to relate population size, individual weight, and water temperature in running waters were tested. Female and male dry weight and specimen numbers of eleven caddisfly species (Trichoptera) collected from 1983 to 1991 in four emergence traps along the Breitenbach (Germany) were related to site specific water temperatures. Water temperature along the stream showed the classical pattern, almost constant near the source and increasing annual variability downstream. Temperature sum (dd = degree days) increased downstream; sums of the last three, six and nine months had a clear seasonality, twelve months sums were almost constant. Greatest upstream-downstream differences occurred in autumn and winter. Comparison of Trichoptera was based on yearly abundance and weight data. Females were heavier in all species but Potamophylax cingulatus. Among sites, weight differences were not detected for Apatania fimbriata. Silo pallipes, Tinodes rostocki, Plectrocne-mia conspersa and for P. cingulatus (♂) and Rhyacophila fasciata (♂) at least in stream sections where they occurred regularly and abundantly. Weight differences were usually significant only between the uppermost or the lowermost, and the remaining sites along the stream. Sericostoma personatum exhibited an almost site by site weight increase downstream. Drusus annulatus (♂, ♀), R. fasciata (9) and P. cingulatus (♀) were lightest at the downstream site, where only R. fasciata occurred regularly. C. villosa (♂, ♀). Potamophylax luctuosus (♂), S. personatum (♂) and Agapetus fuscipes (♂) were lightest at the uppermost site. No single hypothesis explained all results. High individual and population success (high weight or abundance) as predicted by the 'Thermal Equilibrium Hypothesis' occurred in D. annulatus, P. cingulatus and P. luctuosus. In contrast, high abundance and low weight occurred in C. villosa and S. personatum. Individual success seems to depend on a specific fit of genetic pre-adaptations, appropriate physiographical and ecological conditions, and competitive ability; it is not necessarily connected with population success.

Size, weight and abundance of eleven species of caddisfly collected in four emergence traps from 1983-1991 at the Breitenbach (Germany) were analyzed for spatial and temporal patterns. Scrapers were abundant and small, shredders rare but large, predators were in between. Individual weights of most species increased downstream. No weight change along the stream was detected in A. fimbriata, T. rostocki, P. conspersa and R. fasciata. At low discharge, specimen numbers of A. fimbriata and C. villosa decreased, but it increased in P. conspersa. No correlation between discharge and any weight measure occurred. Intra- and interspecific competition was detected only between the scrapers A. fuscipes, A. fimbriata and D. annulatus, with negative effects on size and weight of other species and of competitors. Similar findings in the shredder C. villosa were effects of site specific temperature patterns, not of direct competition. It was evident that dependencies or interactions discovered at individual sites generally did not occur at all sites simultaneously. Inter- and intraspecific competition for a limited food source was detected only in scrapers during periods of low flow. No effects of food shortage was discovered in shredders or predators. Thus, based on the individual and population success of caddisflies, it is argued that the stream community in the Breitenbach was mainly driven by physical forces, temperature and discharge. Only under particular spatial and temporal conditions competition effects do become evident.

Adults of Chaetopteryx villosa (FABRICIUS) (Trichoptera, Limnephilidae) show marked differences in size and weight between sexes at individual stream sites. Size and weight of females increase with distance from the source of the Breitenbach. By rearing specimens from individual egg masses, differences between sexes were attributed to distinct life histories. Males remained longer in larval instars I to III; females spent a greater proportion of the life cycle in instars IV and V. As a result, females were almost twice the size of males. An in-stream enclosure experiment demonstrated that sex, food quality (fine or coarse particulate organic material; FPOM, CPOM), water temperature and, to a smaller extent, origin of specimens determined the size and weight of the developing adults. However, the percent fat content of males and females was unaffected by these factors. Because FPOM and CPOM in the stream were not limiting, size of the adults was determined predominantly by water temperature. Results of the in-stream experiment agreed well with the size and weight patterns observed over a ten-year period in the stream under investigation (Breitenbach). The amount of nutrients invested in the growth of two males was almost identical to that invested in the growth of one female. Maximum size and weight of C. villosa females occurred at sites with the lowest population densities. This pattern reflected the accumulation of degree days rather than a limitation by increased competition for food.

We modelled the total number of individuals of selected water insects based on a 30-year data set of population dynamics and environmental variables (discharge, temperature, precipitation, abundance of parental generation) in a small stream in central Germany. For data exploration, visualisation of data, outlier detection, hypothesis generation, and to detect basic patterns in the data, we used Kohonen's self organizing maps (SOM). They are comparable to statistical cluster analysis by ordinating data into groups. Based on annual abundance patterns of Ephemeroptera, Plecoptera and Trichoptera (EPT), species groups with similar ecological requirements were distinguished. Furthermore, we applied linear neural networks, general regression neural networks, modified multi-layer perceptrons, and radial basis function networks combined with a SOM (RBFSOM) and successfully predicted the annual abundance of selected species from environmental variables. Results were visualised in three-dimensional plots. Relevance detection methods were sensitivity analysis, stepwise method and Genetic Algorithms. Instead of a sliding windows approach we computed the in- and output data of fixed periods for two caddis flies. In order to assess the quality of the models we applied several reliability measures and compared the generalisation error with the long-term mean of the target variable. RBFSOMs were used to denominate and visualise local and general model accuracy. Results were interpreted on the basis of known species traits. We conclude that it is possible to predict the abundance of aquatic insects based on relevant environmental factors using artificial neural networks.

Vingt-deux especes de dipteres aquatiques ont ete recoltees dans seize localites de la Peninsule Iberique. Trois Dixidae : Dixa nebulosa Meigen, D. puberula Loew, D. submaculata Edwards; trois Thaumaleidae : Thaumalea miki Edwards, T. pyrenaica Edwards, T. verralli Edwards; et seize Empididae aquatiques (Hemerodromiinae et Clinocerinae) ; Hemerodromia adulatoria Collin, H. baetica Collin, H. gaditata nov, spec., Wiedemannia mirousei Vaillant, W. fallaciosa (Loew), W. hygrobia (Loew), W. digitato Vaillant, W. tiburica nov, spec., Clinocera barbatula Mik, C. madicola Vaillant, C. tenella Wahlberg, C. nigra (Meigen), C. fontinalis (Haliday), C. stagnalis (Haliday), C. wesmaeli Macquart et Dolichocephala ocellata Costa. Deux especes nouvelles d'Empididae sont decrites et plusieurs especes sont une premiere citation pour l'Espagne ou l'Andorre ou leur presence etait pre. visible, compte-tenu de leur presence dans les Pyrenees francaises.

Summary Nymphomyia succina sp.n., the first fossil nymphomyiid fly (Diptera) from the Eocene Baltic and Bitterfeld amber is described and figured, based on four males. A probably conspecific female from the Baltic amber is also described and figured. With the discovery of this species, a gap in the distribution pattern of extant Nymphomyiidae is closed. It is probable that nymphomyiids colonized the eastern Nearctic Region via the Thule landbridge approximately 25–30 million years before present.

The assessment of properties and processes of running waters is a major issue in aquatic environmental management. Because system analysis and prediction with deterministic and stochastic models is often limited by the complexity and dynamic nature of these ecosystems, supplementary or alternative methods have to be developed. We tested the suitability of various types of artificial neural networks for system analysis and impact assessment in different fields: (1) temporal dynamics of water quality based on weather, urban storm-water run-off and waste-water effluents; (2) bioindication of chemical and hydromorphological properties using benthic macroinvertebrates; and (3) long-term population dynamics of aquatic insects. Specific pre-processing methods and neural models were developed to assess relations among complex variables with high levels of significance. For example, the diurnal variation of oxygen concentration (modelled from precipitation and oxygen of the preceding day; R 2 0.79), population dynamics of emerging aquatic insects (modelled from discharge, water temperature and abundance of the parental generation; R 2 0.93), and water quality and habitat characteristics as indicated by selected sensitive benthic organisms (e.g. R 2 0.83 for pH and R 2 0.82 for diversity of substrate, using five out of 248 species). Our results demonstrate that neural networks and modelling techniques can conveniently be applied to the above mentioned fields because of their specific features compared with classical methods. Particularly, they can be used to reduce the complexity of data sets by identifying important (functional) inter-relationships and key variables. Thus, complex systems can be reasonably simplified in clear models with low measuring and computing effort. This allows new insights about functional relationships of ecosystems with the potential to improve the assessment of complex impact factors and ecological predictions. © 1999 Elsevier Science B.V. All rights reserved.

Twenty nine species of aquatic dance flies (Empididae: Clinocerinae and Hemerodromiinae) were recorded from the Breitenbach (Hesse, Germany) between 1983 and 1993. Although most species emerged in spring and summer, Clinocera (Hydrodromia) stagnalis and C. (H.) wesmaeli were trapped in almost every month. A few species of the subgenus Kowarzia of Clinocera emerged in autumn and early winter. Chelifera pyrenaica had two generations per year in the lower part of the stream, but in the upper reach there was only a spring generation. The distribution pattern along the stream of most of the abundant species was maintained over the entire study period. As an exception, Wiedemannia bohemani was abundant in the middle reach of the stream between 1983-1988, but in the lower reach in 1989-1993. As the amount of Particulate Organic Matter (POM) probably increased the abundance of prey organisms, highest numbers were found in areas with high amounts of allochthonous input. Larvae avoided sandy substrates. Many were found in partly submerged moss carpets on stones, at or below the water level. Females of Hemerodromiinae had higher body weights than males, and specimens in localities near the spring were heavier than those from lower sections of the stream, probably as a result of the temperature pattern of the stream. In Clinocerinae the differences between the sexes, and at different sites, were negligible. Ordination of abundance data, as well as environmental data, showed the dominating influence of 'time' and discharge pattern on the community of aquatic dance flies, and the subordinate influence of water temperature, in a time series of 11 years.

Six new species of Empididae (Diptera) are described from the West Usambara Mts in Tanzania: Brachystoma flavella sp. n. belonging to the subfamily Brachystomatinae; Hemerodromia denticulata sp. n., Drymodromia flaviventris sp. n. and D. bimaculata sp. n. belonging to the subfamily Hemerodromiinae; and Roederiodes tanzaniae sp. n. and Clinocera (Kowarzia) usambarica sp. n. belonging to the subfamily Clinocerinae. R. tanzaniae sp. n. is the first species of Roederiodes to be recorded from the Afrotropical Region.

Bergenstammia aurinae sp. n., a new species of aquatic dance flies (Diptera: Empididae: Clinocerinae) from South Tyrol, Italy, is described and figured.

The following new taxa of Psychodidae (Diptera) are described and figured: Telmatoscopus caribicus sp.n., Trichomyia botosaneanui sp.n., Alepia martinicana sp.n., Pericoma hygropetrica sp.n., Maruina hoguei sp.n. (putative larva and male), Maruina tobagensis sp.n. (putative larva and male), Atrichobrunettia insularis sp.n. and Setomima stylappendiculata sp.n. Arisemus boxi Satchell, 1955 is recorded from Martinique and the description of an interesting larva is provided that cannot be determined at present. All specimens were collected during a collecting trip to the Islands of Martinique and St. Vincent by Dr. L. Botosaneanu (Amsterdam) in February and March 1989.

Two new species of Psychodidae, Trichomyia stephani nov. spec. (subfamily Trichomyiinae) and Telmatoscopus thuringicus nov. spec. (subfamily Psychodinae) collected in Germany are described and figured. The larvae, like those of their close relatives are most probably bound to decaying wood. Cutting down in particular old trees finally axes habitats of many endangered red data list species.

Egg masses of the European net-spinning caddisfly Plectrocnemia conspersa were collected from a small stream, with the object of studying egg incubation and early (first seven days) larval behaviour. Egg masses contained 150-800 eggs (mean 440.2, 95%CL 75.6). Egg incubation period in the laboratory (y days) was related to temperature (x°C) by the equation ln(y) = 3.14 + 0.144 ln(x), taking 93 days at 6°C and 20 days at 18°C. Egg masses incubated in the field hatched as predicted by this equation. The length of individual eggs increased by an average of 17% during incubation. Emergence from the egg took about 30 min, and newly hatched larvae had yolk in their guts which lasted 24-30 h, after which feeding began. Larvae took only live prey. In still water, larvae span silk, ventilated using abdominal undulations, turned in the net, and performed further miscellaneous movements. Newly hatched 'yolky' larvae spent the most time spinning; older larvae resident in the mass of silk near the maternal egg mass car...

Today’s knowledge of worldwide species diversity of 19 families of aquatic Diptera in Continental Waters is presented. Nevertheless, we have to face for certain in most groups a restricted knowledge about distribution, ecology and systematic, particularly in the tropical environments. At the same time we realize a dramatically decline or even lack of specialists being able, having the time or the opportunity to extend or even secure the present information. The respective families with approximate numbers of aquatic species are: Blephariceridae (308), Deuterophlebiidae (14), Nyphomyiidae (7), Psychodidae (∼2.000), Scatopsidae (∼5), Tanyderidae (41), Ptychopteridae (69), Dixidae (173), Corethrellidae (97), Chaoboridae (∼50), Thaumaleidae (∼170), Ceratopogonidae (∼6.000), Stratiomyidae (∼43), Empididae (∼660), Lonchopteridae (2), Syrphidae (∼1.080), Sciomyzidae (∼190), Ephydridae (∼1.500), Muscidae (∼870). Numbers of aquatic species will surely increase with increased ecological and taxonomical efforts.

When the larvae of the caddis flyApatania fimbriata (Pictet) are threatened, drops of fluid appear on their head capsules. The secretions are produced in a gland in the dorsal part of the prothorax. The neck region contains an eversible sac with numerous single setae, groups of 3 setae, or rows of setae on the surface. The secretion is released through two paris of orifices on the lateral sides of the sac. For the most part the secretion is composed of some 30 fatty acids, with the major components having 12–14 carbon atoms and up to 4 double bonds (approx. 1–2 µg secretion per specimen). Biotests with synthetic saturated acids (C6–C12) in a stream and in the laboratory demonstrated a paralysing effect on small invertebrate predators (Rhyacophila sp.,Plectrocnemia conspersa, Hydropsyche sp., larvae, all Trichoptera). In choice experiments,Rhyacophila sp. larvae preferred larvae ofAgapetus fuscipes andDrusus annulatus (Trichoptera) as food as compared withApatania fimbriata larvae. Larger predators, such asDinocras cephalotes (Insecta, Plecoptera) and the fishCottus gobio, did not discriminate betweenApatania fimbriata and other prey species. The use of fatty acids in defensive secretions is interpreted as an adaptation to the running water environment. They are effective repellents againstRhyacophila sp. larvae, the most important predator in the natural environment ofApatania larvae.

The life cycle of Sericostoma personatum (Spence) was studied at 6 °C, 10 °C and 14 °C and at each temperature at 8 and 14 hrs daylength. Embryogenesis was not temperature dependent in the 12°–18°C range. Only 7 of 38 (app. 18%) had a direct development, the rest remained in diapause with partly developed larvae. Hatching success of single egg masses was over 95%. At 6 °C at both LDs, about 452 days are required for larval development. At 10 °C 370 days (LD 8/16), or 320 days (LD 14/10) and at 14° C 319 days (LD 8/16) and 295 days (LD 14/10) were required. Duration of instars III and IV was longer at 6 °C (both LDs), compared with all other groups. Vth instar larvae of the 14 °C (LD 14/10) group grew fastest. Instar VI larvae of the 10 °C short day group developed faster than all others. Instar VII larvae of both 14 °C groups and of the 10 °C long day group develop faster than the rest. Duration of pupal instar is only temperature dependent, regardless of light regime. The field life cycle of S. personatum may require 2–5 years. Larvae are night active. They feed on Coarse Particular Organic Material (CPOM) on the sediment surface at night. They release faeces (Fine Particular Organic Material, FPOM) into the sediment where they rest by day at a few cm depth. Their burrowing behavior thus contributes to the retention of FPOM in the stream channel. Daily food consumption at constant 10 °C is significantly dependent on night length (r 2 = 0.979, p < 0.05). Two factors thus may limit food consumption: in winter, low temperatures, and in summer short nights. The species thus avoids competition by day-active shredders and predation by day-active predators.

Chaetopteryx villosa Fabr. is uni- or semivoltine. The species was reared at 6°C and 10°C (8 h light, 16 h dark = LD 8/16) and at 10°C and 14°C (LD 14/10). Larval instar duration and pupal period decreased with increasing temperature. Instars II-IV were completed within 2-5 wk. Vth instar larvae pupated after two to twelve months. Pupal development required between one and three months. At 6°C no specimens pupated. At 10°C, LD 14/10 accelerated the development of instars II, IV, V and pupae. Head capsule widths were different between laboratory and field specimens. Relative consumption rate (RCR) ranged between 3.07 ± 1.12 (instar II, 14°C) and 0.09 ± 0.05 (instar V 6°C) mg mg-1 d-1. Growth rate, relative growth rate and efficiency of conversion were calculated. In a field experiment fine particulate versus coarse particulate organic material were tested as food sources. FPOM-fed specimens were smaller than those fed with FPOM + CPOM. Pupation was initiated earlier in the FPOM fed group and lasted longer than in the other groups.

The aquatic insect collection of the late Dr. W. Joost contained two new species of Thaumaleidae (Diptera) from the Caucasus Mountains: Thaumalea monikae sp. n. and Thaumalea biacuminata sp. n. These two new species are herein described, and the most abundant species in Dr. Joost's collection, Thaumalea martinovskyi Joost, 1979, is redescribed based on the type material. Figures of male and female genitalia for all species are provided. All three species show morphological similarities to taxa from the Eastern Mediterranean area. Thaumalea monikae is related to the European T. bezzii-species group, T. biacuminata to the T. serrata-group, and T. martinovskyi to T. kyladica Wagner, 1981 and T. malickyi Theischinger, 1979 from the Eastern Mediterranean area.

The assessment of properties and processes in running water ecosystems is a major issue in basic and applied aquatic science and has consequences for environmental management. However, knowledge of the system functions, e.g. temporal and spatial dynamics of physical, chemical, hydro-morphological and biological processes, and species-habitat interrelations are still insufficient. An integrative and prognostic ecological assessment of running waters thus is presently not available (e.g. Bayerisches Landesamt fur Wasserwirtschaft 1998; Resh et al. 1994; Statzner et al. 1994; Townsend and Hildrew 1994; Townsend 1989; Vannote et al. 1980).

Two methods to predict the abundance of the mayflies Baetis rhodani and Baetis vernus (Insecta, Ephemeroptera) in the Breitenbach (Central Germany), based on a long-term data set of species and environmental variables were compared. Statistic methods and canonical correspondence analysis (CCA) attributed abundance of emerged insects to a specific discharge pattern during their larval development. However, prediction (specimens per year) is limited to magnitudes of thousands of specimens (which is outside 25% of the mean). The application of artificial neural networks (ANN) with various methods of variable pre-selection increased the precision of the prediction. Although more than one appropriate pre-processing method or artificial neural networks was found, R 2 for the best abundance prediction was 0.62 for B. rhodani and 0.71 for B. vernus.

Diel patterns in mobility and feeding behaviour of the larvae of the stream-dwelling trichopteran Sericostoma personatum larvae were investigated. Larvae fed at night on coarse particulate organic matter (CPOM) at the sediment surface. In the daytime they rested a few cm below the sediment surface, during which time their defaecation activity affected a release of fine particulate organic matter (FPOM) into the sediment. The amount of faeces (mean particle size = 0.1 ± 0.044 mm, x ± SD, n = 500) introduced into the sediment by the larvae, evaluated in two experiments, was 0.4-0.56 mg day-1. This amount did not differ significantly from the organic input resulting from bacterial activity (0.36-0.64 mg day-1). The presence of S. personatum larvae increased the sediment organic content by 42.9 mg (75.8%) and 59.8 mg (185.6%) AFDW per 16 cm3 sediment over a 90-day period, as compared with control systems containing no larvae.

Thaumalea rivosecchii sp.n., a new thaumaleid (Diptera, Thaumaleidae) from Central Italy is described and figured. Its closest relative is T. gerecki Wagner, from Sardinia.

Wiedemannia graeca sp.n., a new species of aquatic dance flies (Diptera: Empididae: Clinocerinae) from Greece is described and figured.

Heleodromia haenii sp.n., a new aquatic dance fly (Diptera, Empididae, Hemerodromiinae) from France is described and figured. It is a member of the subgenus Illiesiella and readily distinguished from its congeners by the possession of S‐shaped, upright distal part of the periandrium.

The European species of the genus Heleodromia (Diptera, Empididae) are revised. Descriptions and drawings of the following species are provided: H. immaculata Haliday, H. irwini sp.n., H. oldenbergi sp.n., H. schachti sp.n., H. pectinulata (Strobl), and H. banatica sp.n.. For the last two species with differently structured genitalia a new subgenus. Illiesiella is created, type‐species H. pectinulata (Strobl). A key for the European species is provided. The distribution of the species is discussed, and the structure of abdomen and genitalia of both sub‐genera are compared.

The first collections of Psychodidae available from the area of the Caucasus and from Iran have been studied. Seven species are new to science: Bazarella centuretinacula sp. n., Berdeniella caucasica sp. n., Clytocerus grusinicus sp. n., Saraiella ressli sp. n., Satchelliella joosti sp. n., Mormia georgica sp. n., and Philosepedon orientalis sp. n. Most new species are close relatives of European Psychodidae, except Clytocerus grusinicus the affinities of which remain doubtful. Six additional wide‐spread species have also been found: Pericoma blandula Eaton, P. exquisita Eaton, Satchelliella nubila (Meigen), Peripsychoda auriculata (Curtis), Psychoda trinodulosa Tonnoir, and Mormia malickyi Vaillant.

Tonnoiriella mirabilis sp. n. and Caenobrunettia echinoflagellata gen. n. et. sp. n. from the neotropical region are described.

The presence of algae within the cases ofAgapetus fuscipes was investigated. Cases recognised as ‘dirty’ or ‘clean’ with the naked eye had more and less algal growth, respectively. Larvae in the former survived significantly longer when starved in the laboratory. It is suggested that the presence of algae within the cases would be of ecological advantage during periods of flood.

A small collection of Psychodidae from Senegambia, West Africa, contained the following species: the cosmopolitans Tinearia alternata (Say), Psychoda parthenogenetica (Tonnoir), the tropicopolitan Clogmia albipunctata (Williston), Brunettia albonotata (Brunetti), common in tropical Africa and India, and a new species. Setomima senegambica n.sp., is described and compared with the already known species of the genus.

(1984). Notes on Empididae (3). Description of Chelifera siveci sp.n. Aquatic Insects: Vol. 6, No. 4, pp. 244-244.