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We assessed the observed effects of land-use alterations and global warming by analyzing changes in the Odonata community of a Mediterranean stream in northeastern Algeria, sampled at a 25-year interval. Results indicate that species richness has increased from 13 to 21 species. However, the apparent increase in species richness seemed to mirror recent physical and chemical changes brought upon the stream. In particular, these anthropogenic environmental changes seemed to have been driving a large-scale shift in the composition of the Odonata community of Wadi Bouaroug with an influx of widespread, (hemophilic species (Paragomphus genei, Crocothemis erythraea, Sympetrum fonscolombii ,Trithemis spp.) at the expense of rare, stenotypic species (Coenagrion puella, Gomphus lucasii). In the light of impending and challenging climatic scenarios, we urge that steps should be taken to set up more long-term monitoring schemes and research of North African streams that may provide insights into causal mechanisms of global changes.