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Abstract: Here, we present the distribution patterns of aquatic Coleoptera species collected in Central Portugal (240 samples, 136 stream sites) and their most important environmental drivers. A total of 81 species were identified from which 16 were endemic of the Iberian Peninsula confirming the high species richness and importance for conservation of this area. The families with higher species richness were Dytiscidae (24 species), Hydraenidae (16 species), Elmidae (13 species) and Hydrophilidae (12 species). We found six groups mainly based on altitudinal, conductivity and lithology gradients. We found a replacement of families, filling different niches over the catchments environmental gradients. According to the distribution maps, the families Dytiscidae and Hydrophilidae appeared in lowland streams while Hydraenidae were collected in upper stretches of the rivers. Various species appeared widely distributed along the different watersheds, most of them belonging to the families Elmidae and Hydraenidae. The highest species richness was found for the Hydraena, represented by 13 species in our study area. Some Hydraena species tend to co-occur at the same sites and have a high similarity in their distribution. This first study of ecological patterns of Coleopteran species in Portugal brought thus new insights to knowledge of this invertebrate group. [Copyright &y& Elsevier]

We test whether species of western Mediterranean aquatic Coleoptera of the ' Haenydra' lineage (Hydraenidae, Hydraena) originated through: (1) successive periods of dispersal and speciation, (2) range fragmentation by random vicariance, or (3) range fragmentation by geographic isolation owing to a general reduction of population density. Europe. To discriminate between scenarios we use contrasting predictions of the relationship between phylogenetic and geographic distance. The phylogeny was based on 3 kb of four mitochondrial and two nuclear gene fragments of about half of the known species of ' Haenydra', including most western Mediterranean taxa. Divergences were estimated using a molecular clock. The relationship between phylogenetic and geographic distance was tested using bivariate plots, Mantel tests and comparison of the observed phylogeny with the one minimizing geographic distances between species, as measured using Euclidean minimum spanning trees (EMSTs). The monophyly of ' Haenydra' was strongly supported, although its phylogenetic placement was not resolved. ' Haenydra' was estimated to be of late Miocene age, with most species originating during the Pleistocene. In two clades ( Hydraena tatii and Hydraena emarginata clades) there was a significant association between geographic and phylogenetic distance, and the reconstructed phylogeny was identical to that obtained through the EMST, demonstrating a strong non-randomness of the geographic distribution of the species. In two other clades ( Hydraena iberica and Hydraena bitruncata clades) there was no association between geographic and phylogenetic distance, and the observed phylogeny was not the one minimizing geographic distances. In one of the clades this seems to be due to a secondary, recent range expansion of one species ( H. iberica), which erased the geographic signal of their distributions. We show that it is possible to obtain strong evidence of stasis of the geographic ranges of narrow-range endemic species through the study of their phylogenetic relationships and current distributions. In at least two of the studied clades, current species seem to have originated through the fragmentation of a more widely distributed species, without further range movements. A process of range expansion and fragmentation may have occurred repeatedly within the ' Haenydra' lineage, contributing to the accumulation of narrow-range endemics in Mediterranean Pleistocene refugia. [ABSTRACT FROM AUTHOR]