An appraisal of the taxonomy of the potamophreatic mites of Switzerland and of some Southern African fresh water mites [Acari : Prostigmata]

DSc, North-West University, Potchefstroom CampusThis taxonomic study of water mites is divided into five parts; Part I - Techniques, Part II - General characters and Classification, Part III - Systematics, Part IV - Checklists, Part V - Bibliography of Ethiopian water mites. The water mites studied were collected from Switzerland and Southern Africa over the past seven years. The Swiss mites were all potamophreatic and the African mites were all collected from lotic habitats. The collecting techniques are discussed. The Swiss mites were collected from 46 localities in the Jura and Tessin while the African mites come from 118 ' localities in Transvaal, the Cape Province, the Orange Free State, Natal, South West Africa and Rhodesia. The techniques of preparation of permanent mounts, serial sectioning, graphic reconstruction and Scanning Electron Microscopy are discussed. The basic terms used in water mite taxonomy are listed and defined. The general external morphology and taxonomic characters of water mites are discussed and illustrated. A survey of the classification of the higher taxa of the Acari is given and the problematic position of the water mites is discussed. Water mite genera,and to a certain extent families, are stable and well defined taxa. However, the superfamilies both in composition and number, are in a fluid and taxonomically unsatisfactory state. This situation is discussed and it is concluded that the pattern of intrarelationships of water mite families and their relationships with other Acari,will appear only after investigation of features other than exoskeletal structure has been undertaken. An illustrated key to the Ethiopian families is given. Representatives of seven families were studied, i.e., the Torrenticolidae, Hygrobatidae, Unionicolidae, Feltriidae, Aturidae, Momoniidae and Arrenuridae. In each case all the synonyms and the more important literature references are listed for the family, subfamily (where applicable) and genus. The diagnostic characters of the relevant families, subfamilies and genera are given together with a discussion.Doctora