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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.

Eversible pleural sacs were recently discovered in ♀♀ of European species of Rhamphomyia Meigen 1822 (Empididae). In live specimens, they are showily orange. SEM photos show a peculiar surface with numerous setae arranged in whorls. It remains unclear whether they are simply decoration or in combination with pheromones to increase female attractivity. Appendages of male Dolichopodinae are digitate and not covered by hairs or setae. They seem to be restricted to the subfamily Dolichopodinae and probably work together with pheromones.

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.

Bruchomyiinae from Burmese, Baltic, and Caribbean amber are revised. Five new species from Baltic, one from Caribbean and three from Burmese amber are described. Based on recently discovered specimens, additional details and corrections for previously described species are provided. Six species from Baltic amber were combined in Hoffeinsodes gen. nov. ( Hoffeinsodes obtusa sp. nov., H. bifida sp. nov., H. cubicula sp. nov., H. longicauda sp. nov., H. reducta sp. nov. and H. hoffeinsi (Wagner 2006) comb. nov.), based on the fusion of gonocoxites and hypandrium, and a laterally expanded epandrium with posterolateral lobes. Genus Palaeosycorax Meunier, 1905 is re-validated, with Palaeosycorax inexpetatus (Wagner, 2012) comb. nov. included. Caribbean amber species Boreofairchildia dominicana sp. nov. and B. hennigianus (Schluter, 1978) comb. nov. are congeneric with extant genus Boreofairchildia Wagner & Stuckenberg, 2016. Three new and two described species from Burmese amber are combined in Palaeoglaesum gen. nov. ( Palaeoglaesum quadrispiculatum (Stebner et al. , 2015) comb. nov., P. velteni (Wagner, 2012) comb. nov., P. muelleri sp. nov., P. bisulcum sp. nov., P. notandum sp. nov.), based on their small size relative to other Bruchomyiinae, and presence of a Y-shaped aedeagal sclerite. Keys to males of species in particular ambers are provided.

Repeated Quaternary glaciations have significantly shaped the present distribution and diversity of several European species in aquatic and terrestrial habitats. To study the phylogeography of freshwater invertebrates, patterns of intraspecific variation have been examined primarily using mitochondrial DNA markers that may yield results unrepresentative of the true species history. Here, population genetic parameters were inferred for a montane aquatic caddisfly, Thremma gallicum, by sequencing a 658-bp fragment of the mitochondrial CO1 gene, and 12,514 nuclear RAD loci. T. gallicum has a highly disjunct distribution in southern and central Europe, with known populations in the Cantabrian Mountains, Pyrenees, Massif Central, and Black Forest. Both datasets represented rangewide sampling of T. gallicum. For the CO1 dataset, this included 352 specimens from 26 populations, and for the RAD dataset, 17 specimens from eight populations. We tested 20 competing phylogeographic scenarios using approximate Bayesian computation (ABC) and estimated genetic diversity patterns. Support for phylogeographic scenarios and diversity estimates differed between datasets with the RAD data favouring a southern origin of extant populations and indicating the Cantabrian Mountains and Massif Central populations to represent highly diverse populations as compared with the Pyrenees and Black Forest populations. The CO1 data supported a vicariance scenario (north–south) and yielded inconsistent diversity estimates. Permutation tests suggest that a few hundred polymorphic RAD SNPs are necessary for reliable parameter estimates. Our results highlight the potential of RAD and ABC-based hypothesis testing to complement phylogeographic studies on non-model species.

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.

Am Thema «IT-Sicherheit» wird das Verhältnis zwischen Medienbildung und Informationstechnischer Bildung diskutiert: IT-Sicherheit ist Voraussetzung für das Recht auf informationelle Selbstbestimmung. Die Struktur des Internet macht es dabei notwendig, auf den Selbstschutz der Nutzerinnen und Nutzer zu setzen. Die Fähigkeit zum Selbstschutz muss durch Sicherheitsbewusstsein ergänzt werden. Man benötigt ein adäquates Modell von Computern und Computernetzen, um die Offenheit dieses neuen «Kommunikations- und Sozialraumes» zu erfassen. Die Vermittlung von Sicherheitsbewusstsein und Sicherheitskompetenz im Umgang mit den Informations- und Kommunikationstechnologien wird damit zu einem wichtigen Bestandteil von Medienkompetenz. Hinzutreten muss die Auseinandersetzung mit dem Recht auf informationelle Selbstbestimmung und der Erwerb kommunikativer Kompetenzen für das Internet.

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.

1-Acyl-4-benzylpyridinium salts 4 containing nonnucleophilic anions X– such as CF3SO3–, FSO3–, and BF4– can be generated quantitatively and in situ from 1-acyl-4-alkylidene-1,4-dihydropyridines 1a–f and the corresponding acid, HX. The BF4– salts reveal an interesting and unexpected thermal instability which allows the convenient synthesis of carboxylic acid fluorides 5b–f. This procedure offers advantages over known methods: All operations can be performed in a standard glass apparatus and do not require high pressures. The formation of RCOF 5 is assisted by the pyridine moiety of 4, which splits off and functions as a Lewis base to intercept the BF3 acid. The structural and electronic relationships as well as dominating differences between the very reactive cations of 4 and their almost “inert” uncharged precursors, the dihydropyridines 1, are discussed both on the fundament of experimental evidence (X-ray structures of 1f and the extremely reactive and very labile 4f) and theoretical investigations (ab initio and DFT MO calculations).

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.

The following new Psychodidae were collected by W. Joost, during a visit in Colombia: Arisemus guhli spec, nov., Arisemus roessleri spec, nov., Arisemus obandoni spec, nov., Arisemus martinezi spec, nov., Psychoda bogotensis spec, nov., and Maruina colombicana spec. nov. In addition, Clogmia albipunctata (Williston), Tinearia alternata (Say), Paramormia spec, and Psychoda spec, were collected.

Global climate change will affect the climate of the Bonn region. The likely forecast for the next five to ten decades shows a climate similar to that of present day northern Italy, that is, a yearly average temperature increase of 2 K. Hotter, earlier and longer dry periods in late spring and summer, increased and stronger precipitation, and warmer rainy winters all require the definition and implementation of strategies and measures for resilient urban structures. The administration of the City of Bonn initiated this process in April 2010 with an expert hearing and a workshop on climate change and city planning. Stadtklima, the recently published manual of the Ministry of Environment North Rhine-Westphalia, features a comprehensive compilation of possible actions and instruments, based on a field test in the industrial and urban region of Ruhrgebiet. The next steps in Bonn will include the involvement of public, political and economic stakeholders in the development of the general principle of ‘resilient city’ and to provide environmentally sound and healthy living conditions in Bonn for the next five to ten decades. Next steps also include the installation of checklist procedures, the improvement of early information and cooperation processes, and the definition of fields of action and criteria for resilient urban structures within the cityscape, such as architecture, traffic ways, water supply, sewer systems, and parks and greens.

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

Absolute Raman scattering activities of aqueous solutions of sodium arsenate and sodium selenate have been measured against NaClO 4 as an external standard. Electro-optical parameters (EOPs) for the AsO and SeO bonds were calculated. Changes of the previously published force fields (GVFF) were necessary to adjust the eigenvectors to the experimental frequencies and intensities in aqueous environment. Equilibrium bond polarizabilities were estimated from refractive index measurements in connection with Raman intensities of bending modes. The EOPs of these two isoelectronic compounds are discussed in comparison with the series phosphate, sulphate, perchlorate.

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 aim of projection pursuit (PP) (Friedman and Tukey 1974, Huber 1985, Jones and Sibson 1987) is to find low (1-3)-dimensional projections showing the most interesting views of high-dimensional data. To reach this goal, many projections are calculated and rated by an objective function, a so called projection index I. Dependent on I, this method is able to characterise the high-dimensional data from different points of view (Fig. 6.3.1). To find good projections it is necessary to maximize I. There are several ways to do this: Gradient Algorithms (Friedman 1987), Simulated Annealing (Montanari and Guglielmi 1996) or Genetic Algorithms (Crawford 1991, Guo et al. 2000). The application of PP has some advantages over other methods. Although the projections are linear, the index may be non-linear, facilitating the detection of non-linear connections in the data. By choosing different and suitable indices, PP is able to provide various views of the data. One important feature of the index functions is robustness; this enables PP to be insensitive to outliers. Projection vectors from previous analysis can be used to view and analyse another data set from the same viewpoint. The multivariate analysis method PP can be used to classify data, comparable to supervised and unsupervised learning in artificial neural networks, but with reproducible results.

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).

The Bosumtwi crater in Ghana is a ~1.05 million year old, very well-preserved complex meteorite impact structure of approximately 10.5 km rim-to-rim diameter. The interior of the structure is largely filled by Lake Bosumtwi, and the crater rim and the environs of the crater are covered by dense tropical rainforest. Thus, direct geological study of this structure is not easy; but remote sensing and geophysical data can be used to better constrain the surface and subsurface geology. Landsat Thematic Mapper (TM) data reveal detailed structure of the crater rim, including arrays of radial, concentric, and tangential or oblique fractures. In all data sets, the presence of an apparent ring feature at ~10–11 km from the crater center is visible. Digitised topographic information and, to a lesser extent, ERS-1/2 radar data provide an improved picture of the crater morphology. A digital elevation model (DEM) for the wider Bosumtwi crater area also reveals the presence of a subdued elevation feature at about 10–11 km radial distance from the lake center, which, in the western area, coincides with the distribution pattern of vegetation. Perspective views of the DEM and other remote sensing data suggest the existence of a further structural feature at 17–19 km distance from the crater center, and which is mainly visible in the southeast sector. An “outer rim“ topography is also known from other impact structures, for example, the Elgygytgyn crater in Russia; the origin of this feature is still debated, but the existence of two apparent ring features may suggest that they represent ring faults caused by the impact compression.

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.

Hemerodromia slovenica sp.n. a new species of the aquatic dance flies (Empididae: Hemerodromiinae) from Yugoslavia, is described and illustrated.

In recent years several Neotropical Psychodidae Psychodinae were collected from Bromeliaceae. These plants are a kind of aquatic microcosmos and harbour a diverse and probably specialized fauna (Frank & Lounibos 2009, Kitching 2000, Richardson 1999). Quite a number of psychodids collected from Bromeliaceae is from genus Arisemus (Satchell, 1955). In some cases adults were reared from larvae collected in bromeliads, so that both stages were associated Wagner et al. 2008; Wagner et al. accepted. From some other species and genera it is known or supposed that their habitat is related to bromeliads (more information in Quate & Brown 2004, Frank et al. 2004). Additional information with description of a new species can be found in Wagner & Hribar (2005). Remarkably one newly described species was transported with a bromeliad from Brazil via the Netherlands to Sweden, where larvae or eggs developed to the adult stage and were collected in a terrarium (Wagner & Svensson 2006). So it appears that the small water bodies in tank bromeliads and other plants or the high atmospheric humidity in the environment of Tillandsia plants provide a sufficient environment for successful development of psychodids, at least in the Neotropical region. Here we report about another new species collected from bromeliads in Florida that belongs to the remarkable genus Neurosystasis Satchell, 1955, of which so far only two species were known: N. terminalis (Satchell, 1955) from Jamaica, and N. amplipenna (Knab, 1914) from Cuba. Quate & Brown (2004) mentioned 3 females from Orange County Florida, U.S.A. collected from Tillandsia utriculata (Bromeliaceae) where larvae live in the leaf axils. Most probably these females are not N. amplipenna (Knab, 1914) but belong to the new species described below.

Es ist wenig realistisch, darauf zu hoffen, das es eines Tages ein Fach Medienpadagogik in unseren Schulen gibt. Daruber zu klagen, wurde jedoch voraussetzen, das ein eigenes Fach sinnvoll und wunschenswert ist. Fur einen solchen Wunsch spricht das Schicksal von Unterrichtsprinzipien und facheruber-greifenden Aufgaben. Fixiert auf den jeweiligen Fachhorizont verlassen sich Lehrerinnen und Lehrer im Normalfall darauf, das irgendwo in einem anderen Fach diese Aufgabe schon irgendwie miterledigt wird. Andererseits last sich schnell aufzeigen, wie wenig ein isoliertes Fach Medienpadagogik ausrichten konnte. Dies zeigt ein kurzer Blick auf den gangigen Umgang mit Medien und Medienerfahrungen.

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.