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International audience; A survey of the macro invertebrates of three brooks harbouring the white-clawed crayfish was conducted in Haute-Vienne department (France). Its aim was to increase our understanding of these ecosystems to help the conservation of A. pallipes. These brooks run through pastoral areas with well-developed riparian vegetation, which offers an important shade. Water temperature, dissolved oxygen concentration, pH, and conductivity fell within the ranges found for this species. A total of 34, 31, 29 taxa and 1502, 1364, 2707 individuals of macrobenthos were collected in Holme, Besque and Bellecombe streams, respectively. Results showed good to very good water quality with IBGN scores ranging from 15 (Bellecombe) to 17 (Holme and Besque), reflecting a limited impact of the anthropogenic disturbances. Taxa diversity were high for Holme and Besque with Shannon index around 3.2, translating a great heterogeneity of habitat and an equilibrated faunal community. Bellecombe showed a limited diversity with Shannon index of 1.42, resulting from the presence of numberous Chironomidae. This brook suffers probably weak organic pollution which could be related to the low water flow observed during the sampling. The similarity test according to Jaccard index showed high percentage of common taxa among ETP (Ephemeroptera-Trichoptera-Plecoptera) between all sites. The high similarity of benthic macroinvertebrate communities could be an useful criteria to identify brooks for restocking purpose.

The phylogenetic relationships of the genus Austropotamobius were reviewed by the compilation of two recent genetic studies based on the partial nucleotide sequence of the mitochondrial RNA 16S gene. The results showed a well-resolved phylogeny revealing four distinct clades: A1, A2, A3 and B, supported by high bootstrap values. The clades A (including A1, A2, A3) and B are separated by a high genetic divergence (5%). In accordance with morphological and nuclear data, two species could be defined: A. italicus and A. pallipes, respectively. The average of genetic divergence within the major group A and B was 2.1% ± 1.2 and 0.9% ± 0.6 respectively. Three clades A1, A2 and A3 correspond mainly to crayfish sampled from Austria-Switzerland, South of Balkans and Italy-Spain respectively. On the basis of morphological, genetic and distribution data, a new systematic - based on two species A. pallipes and A. italicus with 3 subspecies A. i. carinthiacus, A. i. carsicus and A. i. italicus - could be proposed for the white-clawed crayfish species complex. We rejected the specific status of A. berndhauseri and A. i. lusitanicus given to the Swiss and Spanish crayfish respectively.