Genetic and morphological variation in the endangered crayfish species, Austropotamobius pallipes (Lereboullet) (Crustacea, Astacidae) from the Poitou-Charentes region (France)

The white-clawed crayfish, Austropotamobius pallipes, an endangered species in Europe, was surveyed for genetic and morphological variation as part of a larger project aimed at clarifying its French stock structure. Analysis from four morphological characters discriminated two groups, one including the 8 stream populations and the other comprising a single pond population. Total mitochondrial DNA variation was examined by RFLP analysis using 11 restriction enzymes for 120 animals sampled from these 9 populations located in Poitou-Charentes region. Among the three haplotypes revealed, two were found in animals sampled from brook populations and the third haplotype was only found in individuals from the pond population. Mitochondrial DNA nucleotide diversity values within species ranged from 0.57 to 1.31%. The analysis of genetic variance showed no structuring of genetic variation by hydrographic basins and could reflect the impact of translocations by man although other explanations are possible.