Abstract: Gvaudan, A., Lewin, J.-M. & Delforge, P.- Contribution to the knowledge of the Epipactis phyllanthes species group: delimitation, ecology and distribution of Epipactis fageticola (Hermosilla 1998) J. Devillers-Terschuren & P. Devillers 1999 [ Natural. belges 82 (Orchid. 14) (2001): 39-104]. Since 1997, numerous records of Epipactis phyllanthes s.l. or s. str. were published outside the Atlantic zone in the Iberian Peninsula (mainly upper Ebro basin and Cantabrian range) and France (mainly department of Pyrnes-Orientales and Rhne basin), as well as descriptions of a new taxa apparently very close to E. phyllanthes, E. phyllanthes var. fageticola, from Cantabrian beech forests, or E. stellifera and E. Òrhodanensis with white flowersÓ, both from the upper Rhne basin, in Switzerland. Research in France (departments Ain, Drme, Pyrnes-Orientales, Savoie, Vaucluse), Switzerland (cantons Genve and Vaud), and Spain (provinces Burgos and Logroo) has led to the identification of all that different taxa with one species of the E. phyllanthes group, which must be named Epipactis fageticola (Hermosilla 1998) J. Devillers-Terschuren & P. Devillers 1999, since Epipactis viridiflava U. Lw 1969, described from Switzerland, seems to be synonym of E. leptochila (Godfery 1919) Godfery 1921. The main taxonomical changes in the E. phyllanthes species group from the E. phyllanthes description in 1852, and the inconsistencies of E. phyllanthes determinations in Spain are evoked. Detailed descriptions of each population of the 22 sites visited is given as well as a list of 107 published sites which concern certainly or very probably E. fageticola. Critical analyses documented by unpublished materials are made for mentions of France (Bouches-du-Rhne), Spain (Galice, Castilla-Len, Andalusia), and Portugal. A precise description of E. fageticola morphology, ecology and distribution is made. Attention is drawn to the inaccuracies in field observations leading to miscontructions; some characters, as the minute serrations of the leaves margin, are redefined; others, sometimes used, as the anther necrosis, are ineffective and rejected. A detailed diagnosis is given. With that new precisions, the delimitation of E. fageticola beside E. phyllanthes, E. fibri, E. gracilis (E. phyllanthes species group) E. campeadorii (E. leptochila species group), and E. rhodanensis (E. helleborine species group) is clarified again. E. fageticola appears as a ÇTethyan speciesÈ of the E. phyllanthes species group, widely distributed in south-western Europa. E. phyllanthes is confirmed as a strictly Atlantic species, and E. rhodanensis, which possesses always purple tinged pedicels, as full member of the E. helleborine species group.
Key-Words: Orchidaceae; genus Epipactis, Epipactis phyllanthes species group, Epipactis fageticola, Epipactis fibri, Epipactis gracilis, Epipactis phyllanthes, Epipactis stellifera, Epipactis persica, Epipactis helleborine species group, Epipactis rhodanensis (= E. hispanica var. hispanica), Epipactis leptochila species group, Epipactis campeadorii (= E. hispanica var. viridis), Epipactis viridiflava; Flora of France, Portugal, Spain, Switzerland.