The water mite Rutripalpas limicola Sokolow, 1934: new data on morphology and biology, and considerations on the systematic position of the monotypicfamily Rutripalpidae (Acari, Hydrachnidia)

New information is given on the morphology of Rutripalpus limicola Sokolow, 1934, including the first descriptions of larvae and deutonymphs, and rede scription of adults in both sexes. Genital flaps of Rutripalpus males are f used forming a penis-like hinged genital tube unique in water mites. A char acter analysis of all life-cycle stages indicates an isolated position of R utripalpidae, with phylogenetic relations to Bandakiopsis Smith, 1979, a ge nus at present placed in the polyphyletic family Anisitsiellidae, and to th e family Teutoniidae. Larvae attributed here to Rutripalpus were found atta ched to larvae of ptychopterid midges, representing the first record of wat er mite larvae parasitizing that dipteran family. Our finding of the specie s in Montenegro (Yugoslavia) is the third record from Europe and the first record from the mediterranean area.