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To determine the Amphipoda (Crustacea) fauna of the inland waters of Western Anatolia, Marmara and the Turkish Thrace Region, field studies were conducted between May 2014 and March 2019. Seven field studies were conducted. Samplings were conducted at 291 localities and amphipod specimens were found at 127 of them. As a result, 11 amphipod species (Echinogammarus stockiG. Karaman, 1970, Gammarus aequicauda (G. Karaman, 1970), Gammarus anatoliensis Schellen-berg, 1937, Gammarus arduus G. Karaman, 1975, Gammarus balcanicus Schäferna, 1923, Gam-marus dorsosetosus Mateus & Mateus, 1990, Gammarus gonensis Özbek, 2016, Gammarus komareki Schäferna, 1923, Gammarus lacustris G.O. Sars, 1863, Gammarus pulex pulex (Linnaeus, 1758), Gammarus uludagi G.S. Karaman, 1975) were determined. The new records can be listed as: E. stocki for Ekinanbarı, G. anatoliensis for Uşak, G. arduus for Bolu and Düzce, G. balcanicus for Kocaeli and Sakarya, G. dorsosetosus for Bolu, G. gonensis for Istanbul and Manisa, G. komarekifor Düzce and Kocaeli, G. lacustris for Istanbul, G. pulex pulex for Bolu, Kırklareli, Kocaeli, Sakarya and Uşak, and G. uludagi for Aydın, Bilecik, Sakarya and Yalova provinces. The observed morpho-logical features and the detailed drawings of the determined taxa are presented. Additionally, a map showing the distribution of the obtained species is also given.

The current status and annotated checklist of fresh- and brackish-water amphipod species inhabiting the inland waters (streams, lakes, ponds, lagoons, subterranean waters, etc.) of Turkey is presented. Totally, 171 papers, 3 books, 3 book chapters, 5 conference papers, 2 projects, 3 PhD and 3 MSc thesis were examined in the present study. As the result of the previous records, 201 taxa comprising 121 amphipods (16 families, 31 genera), 27 isopods (9 families, 13 genera), 9 mysids (1 family, 5 genera), 4 tanaids (3 families, 4 genera) and 40 decapods (16 families, 18 genera) were compiled. All the previously recorded localities of each taxon were listed in detail. The endemic taxa and the doubtful records were indicated and discussed. Twenty maps showing the distribution of reported species were also presented.

Times Cited: 36; International audience; Mitochondrial DNA nucleotide sequence analysis was used to determine the extent of genetic differentiation among six species of the genus Gammarus (Crustacea, Amphipoda) common in France (G. fossarum, G. pulex, G. Lacustris, G. wautieri, G. roeseli, G. marinus). From 23 different populations, 104 specimens were compared to examine their taxonomic status and their phylogenetic relationships. Nucleotide sequences for a 376-base segment of the cytochrome c oxidase subunit I (COI) gene were obtained through direct sequencing of amplified DNA. The strong sequence variability found at the interspecific level, generally masked by morphological or ecological similarities, is consistent with that observed for other crustaceans and supports existing species classifications. A high level of genetic variation was observed at the intraspecific level, suggesting that the COI gene will be a powerful marker for amphipod population biology. Based on the mitochondrial DNA results, we propose a phylogenetic hypothesis of the relationships among the six studied species, which is discussed in biogeographic and evolutionary terms. (C) 1997 Academic Press.

International audience; As an example of the relative impact of a specific ambient parameter on intraspecific phenotypic differentiation, the contribution of environmental sources of calcium on the geographic variation between alpine populations of the freshwater crustacean Gammarus fossarum was investigated through a comparative analysis of six different populations in the torrents of the Grenoble region of France. Major differences in water calcium levels were observed in correlation with lithological differences (average 13.6 mg/L in the crystalline massif of the Belledonne and 83.4 mg/L in the limestone areas of the Chartreuse and Vercors). The comparative analysis of the populations was performed through field and laboratory experimentation at morphometrical and ecophysiological levels. Uniform samples of male adult specimens from six different sites (two sites in the Belledonne, two sites in the Chartreuse, and two sites in the Vercors) were compared using three easily measurable parameters: maximum dry mass, duration of the molt cycle, and calcium balance during the molt cycle. Animals from waters that flow over limestone show a larger maximum size and a longer molt cycle than those from waters that flow over crystalline rocks. Spectrophotometrical analysis of their calcium balance during the molt cycle reveals that, whereas all animals are equally calcified during the intermolt, the decalcification during the premolt and the recalcification during the postmolt are more rapid in animals from limestone areas than in those from crystalline sites. Translocation experiments in both natural and artificially calcium-enriched waters confirm these differences. A significant increase in the duration of the molt cycle was observed in animals translocated to water of lower calcium concentration and vice versa, whereas no significant difference was observed between controls and animals translocated into water of comparable calcium concentration. Current results, supported by such a new synthetic experimental approach, indicate that variations in water calcium levels may generate important ecophysiological differentiation between populations, which may suggest a possible influence of environmental calcium on the geographic distribution of Gammarus fossarum.