The paper proposes a new biological method for assessing the quality of lakes. It is based on the comparison of littoral and profundal macroinvertebrate communities sampled in soft sediments. Two depths were sampled: one at the littoral zone (Zl = 2m) to define a littoral index (Bl ) related to the biogenic potential of the lake (quantitative data), the other at the deep zone (Zf = 0.66 Zmax) to define a taxonomic deficit index (Df ) connected with the quality of the water-sediment interface in deep zone (qualitative data). These two indexes were combined in a Lake Biotic Index (LBI), with a range from 0 to 20, which gives an evaluation of the biogenic capacity of a lake to the development of macroconsumer communities. Using the Bl and Df values any lake can be plotted on a typological graph which is helpfull to characterize lakes both quantitatively (oligo- to polybiotic) and qualitatively (eu- to dysbiotic). Lake Châlain (French Jura) is presented as an example of the method application with its macrofauna and the index calculation. Then, this lake was included in the typological graph with nine other French lakes studied using the same method. Each lake, characterized by its Bl, Df and LBI values, can be compared to the others in a typological scheme. The proposed indexes are discussed and bases for interpretation of the results are presented. The proposed classification of lakes gives an evaluation of their biogenic capacity concerning macroconsumers and can be usefully compared with other classifications, especially with trophic and sediment types, in functional studies as well as in lake diagnosis, in the context of the Water Framework Directive (Directive 2000/60/CE).

Ecotoxicological studies with cladocerans frequently assess the individual growth of the organisms. Measures upon living organisms should be avoided once they can lead to their death or affectation, therefore constraining the results. In this way, and considering that cladocerans species go through series of moults along their life cycle, measures upon the moult are preferred in almost all the studies. Thus, the establishment of allometric relations is required to enable feasible estimations of diverse growth parameters. Exopodite and total body length of two autochthonous (Daphnia longispina; Ceriodaphnia pulchella) and two standard (Daphnia magna; Ceriodaphnia dubia) living daphnids were registered. Regression analysis was applied in order to establish a relation between the two allometric measurements in each species. As high R-squared values were reached in all species, the obtained equations can be used as reference for estimations of body length in face of the «moult» exopodite length measure. Consequently, this work provides a support reference for ecotoxicological studies performed in lab with these species.

South-eastern France is highly interesting for hydroentomology, in particular for caddisflies. Its lower zones are communication corridors for the fauna of the Apennines on one hand, and for that of the Pyrenees and Cantabric Cordillera on the other hand. At the same time, its high mountain massifs are inhabited by a fauna including endemic elements vicarious with other Alpine massifs, and having sometimes a relict character. The present paper insists on the most interesting discoveries made by studying important collections from springs, streams and mountain rivers in various parts of the zone: taxa new for science (Plectrocnemia geniculata prealpina n. ssp., Hydropsyche subalpina n. sp, Drusus biguttatus teunisseni n. ssp., Alpopsyche n. g.), taxa new for the French fauna (Tinodes antonioi, T. dives consiglioi, Hydropsyche pictetorum, H. tenuis, Ylodes canus), and additional information (morphology, distribution) for a number of species.

Collections of Chironomidae from aquatic habitats on the Azores islands of São Miguel and Flores during August 1997 and on São Miguel, Terceira and Graciosa in September-October 1998, yielded 33 species-level taxa. Representatives of 16 taxa in three subfamilies are new generic / species records for the Azores archipelago: Tanypodinae - Procladius (Holotanypus) choreus (Meigen), Paramerina sp. griechenland, Zavrelimyia sp.; Orthocladiinae - Metriocnemus (Inermipupa) carmencitabertarum Langton et Cobo, Orthocladius (Eudactylocladius) sp., Psectrocladius limbatellus (Holmgren), Psectrocladius sp., Pseudorthocladius sp., Smittia contingens (Walker); Chironominae - Chironomus cingulatus Meigen, Chironomus cf annularius (De Geer), Glyptotendipes barbipes (Staeger), Glyptotendipes pallens (Meigen), Polypedilum nubifer (Skuse), Micropsectra sp. (cf lindrothi Goetghebuer), Paratanytarsus grimmii (Schneider). A revised checklist is provided, incorporating and updating previous records.

73 species and subspecies are reported from the North West of the Iberian Peninsula, including 10 new taxa described in the last four years. 14 species are new for the Cantabrian Cordillera, 1 for Galicia, 9 for the Sierra de la Demanda and 2 for the Sierra del Moncayo. The systematic status of some species is modified: Protonemura pyrenaica pyrenaica and P. pyrenaica asturica are restored to specific level; Leuctra lusitanica is considered as a subspecies of L. lamellosa; Nemoura cinerea umbrosa is a valid subspecies of N. cinerea cinerea. The stonefly faunistic lists of the Cantabrian Cordillera, Galicia, Demanda and Moncayo are updated. Species distribution patterns and faunistic relations with the neighbouring regions are analyzed. Classification and ordination analyses based on species presence, enable identification of bioclimatic and biogeographical patterns of Plecoptera distribution in the North of the Iberian Peninsula.

Many freshwater algae are parasitized by aquatic fungi belonging to the Chytridiales Order. The top-down effects of parasitism result in individual losses within algal populations. We present data on the parasitism of the diatom Asterionella formosa Hassall by chytrids, occurring in response to hydrodynamic disturbances and the architecture of the algal host on the landscape scale. Among a series of nine reservoirs, the observed pattern of parasitism depends on the levels of hydrodynamic disturbance: the rate of parasitism is higher at intermediate disturbance levels. A. formosa cells are not randomly parasitized. Whatever the disturbance levels, fungi were found to mostly parasitize cell clusters forming non-stellate colonies.

The diagnostic features of the African species of the monotypic subfamily Diplodontinae K. Viets, 1936 are discussed. D. chutteri K.O.Viets, 1980 obviously represents the outgroup of all remaining species. D. scapularis Dugés, 1834 and D. semiperforatus Walter, 1925, both in Africa restricted to the palaearctic part, are sister species characterized by synapomorphic character states in the genital field and shape of palps and legs. Diplodontus schaubi gracilirostris Lundblad, 1942 is elevated to species rank. Two species from Madagascar are described as new to science, with morphological characteristics and a habitat preference so far unknown in this genus. Obviously, they have evolved particular adaptations under long term stable conditions in isolated rain forests of N and E Madagascar. A new diagnosis is proposed for the subfamily Diplodontinae K.Viets, 1936.