A faunistic study of water mites (Hydrachnidia and Halacaridae) from southern Norway

Abstract

Targeted sampling of a broad range of freshwater habitats over the past five years, combined with screening of recent records available in online databases, substantially increased the number of water mite species known to Norway. Among the 190 species now recorded (187 Hydrachnidia and 3 Halacaridae), 47 are new to Norway, while 21 are recorded from Fennoscandia for the first time. Partial COI-sequences (DNA barcodes) of 110 species were generated in our project, and comparative analyses showed indications of cryptic species diversity for ten species. We provide an updated checklist for the Norwegian water mite fauna with comments on distribution and ecology. Included are detailed locality records, ecological habitat characteristics and some important physicochemical parameters for the collecting sites visited by us. For species of particular interest, open taxonomic questions and needs for further research are discussed.