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tChironomidae are among the most conspicuous and ecological diverse group of freshwater invertebrates.They may dominate unimpacted communities in abundance and biomass, accounting for more than 50%of macroinvertebrate species in standing and flowing waters. In deep zones of eutrophic lakes and highlyhuman-impacted streams, they are often the only family of aquatic insects remaining. In bioassessmentprogrammes, Chironomids are often identified at the family and subfamily levels, due to difficulties inthe taxonomic identification of larvae resulting from a high intrinsic morphological similarity. This maypotentially result in bias as, similarly to Ephemeroptera, Trichoptera or Plecoptera, Chironomidae species,which are replaced along natural and human-impacted gradients due to differences in their ecologicalrequirements. Recently, multiple trait-based approaches have been proposed to complement taxonomic-based assessment of streams and rivers using macroinvertebrates. However, the lack of specific traitinformation for Chironomidae prevents their use in the functional assessment of communities. Therefore,here, we aimed to: (1) develop a trait database for European Chironomidae genera that can be used infuture bioassessment and ecological studies; (2) evaluate, by multivariate analyses, whether our newdatabase provides additional information on Chironomidae compared to the trait information providedin the commonly used European trait database (Tachet et al., 2010); and (3) determine whether thenew information on Eltonian traits (proxy to biological traits) translates the most accepted phylogeneticrelationships among Chironomidae subfamilies. We gathered information on 744 species and 178 genera,for 37 traits covering 186 trait categories, and found substantial differences between our database and thecommonly used European trait database. In addition, available information on traits was not always inagreement with phylogenetic relationships among subfamilies. Orthocladiinae and Chironominae whichare considered sister groups in evolutionary terms actually showed confident trait relatedness based onEltonian traits tree while the remaining relationships between subfamilies are questionable. In addition,different traits can occur in closely related taxa depending on the environmental drivers operating ontheir habitats. Our study reveals that the usually accepted redundancy within the Chironomidae familyand subfamilies must be a product of averaging the information from finer taxonomic resolution addedto the substantial lack of information for this insect group.

J Biol Inorg Chem (2004) 9: 145–151 DOI 10.1007/s00775-003-0506-z We report the characterization of the molecular properties and EPR studies of a new formate dehydrogenase (FDH) from the sulfate-reducing organism Desulfovibrio alaskensis NCIMB 13491. FDHs are enzymes that catalyze the two-electron oxidation of formate to carbon dioxide in several aerobic and anaerobic organisms. D. alaskensis FDH is a heterodimeric protein with a molecular weight of 126+/-2 kDa composed of two subunits, alpha=93+/-3 kDa and beta=32+/-2 kDa, which contains 6+/-1 Fe/molecule, 0.4+/-0.1 Mo/molecule, 0.3+/-0.1 W/molecule, and 1.3+/-0.1 guanine monophosphate nucleotides. The UV-vis absorption spectrum of D. alaskensis FDH is typical of an iron-sulfur protein with a broad band around 400 nm. Variable-temperature EPR studies performed on reduced samples of D. alaskensis FDH showed the presence of signals associated with the different paramagnetic centers of D. alaskensis FDH. Three rhombic signals having g-values and relaxation behavior characteristic of [4Fe-4S] clusters were observed in the 5-40 K temperature range. Two EPR signals with all the g-values less than two, which accounted for less than 0.1 spin/protein, typical of mononuclear Mo(V) and W(V), respectively, were observed. The signal associated with the W(V) ion has a larger deviation from the free electron g-value, as expected for tungsten in a d(1) configuration, albeit with an unusual relaxation behavior. The EPR parameters of the Mo(V) signal are within the range of values typically found for the slow-type signal observed in several Mo-containing proteins belonging to the xanthine oxidase family of enzymes. Mo(V) resonances are split at temperatures below 50 K by magnetic coupling with one of the Fe/S clusters. The analysis of the inter-center magnetic interaction allowed us to assign the EPR-distinguishable iron-sulfur clusters with those seen in the crystal structure of a homologous enzyme.