Abstract. Devillers, P. & Devillers-Terschuren, J.- Dactylorhiza sudetica in the Giant Mountains [Natural. belges 81 (Orchid. 13) (2000): 331-338 + 4 figs]. Dactylorhiza sudetica is a long-known taxon, described by Reichenbach in1851 on the basis of a type taken in the Sudeten, a biogeographically remarkable Hercynian range located astride the present Polish-Czech border. The epithet has been used erratically to designate both Alpine and Fenno-Scandian taxa. At the same time, Sudetic populations were often designated locally by names borrowed from the Scandinavian flora, such as D. psychrophila. These vagaries probably reflect the unique character of the high-altitude ecosystems of the Sudeten, formed of both arctic and Alpine elements accompanied by an impressive endemic cort¸ge. Confusion over Dactylorhiza sudetica seems to persist in spite of detailed studies conducted in Central Europe. The most frequent present-day usage is to employ D. sudetica for the Alpine populations described by Tyteca & Gathoye (1990b) under the name of Dactylorhiza savogiensis, and to call the Sudeten populations Dactylorhiza fuchsii ssp. psychrophila or Dactylorhiza psychrophila. Having seen D. sudetica in its habitat, with a field experience of some of the Scandinavian and Alpine taxa with which it is often associated, we review the characters of the Hercynian species and express our conviction that there is no reason to link it to another taxon, Scandinavian or Alpine. Dactylorhiza sudetica appears to be an uncommon species, limited to few stations with small numbers of individuals. Its distribution is probably similar to that of Pedicularis sudetica for which Krukowski (1997) has documented present-day scarcity, considerable recent decrease and strong sensitivity to habitat degradation, particularly that induced by atmospheric pollution. D. sudetica should thus be considered a fragile species and be placed on the list of target species to be taken into account in the management plans of the transborder biosphere reserve that encompasses the Krkonose and Karkonosze national parks.

Key-words: Orchidaceae, genus Dactylorhiza, Dactylorhiza sudetica, Czech Republic, Hercynian ranges, Sudetic Mountains, Sudeten, Krkonose, Karkonosze, Giant Mountains, Riesengebirge.