Epipactis Zinn, 1757

D. M. Moore (ed.), 1980, CCIII Orchidaceae, Flora Europaea, Vol 5: Alismataceae to Orchidaceae, Camebridge: Cambridge University Press, pp. 325-350 : 326-327

2. Epipactis Zinn 1

( Helleborine Miller )

Plants with horizontal or vertical rhizome and numerous fleshy roots. Stem leafy. Flowers pedicellate, patent or pendent, in more or less secund spikes. Perianth-segments free, patent or connivent, the inner similar to the outer but smaller. Labellum with concave or cupuliform basal part (hypochile) separated by narrow joint or fold from the flat, forward-directed distal part (epichile), with basal tubercles or ridges; spur absent. Column short. Rostellum usually large and globose, sometimes absent. Viscidia absent; bursicles absent.

A difficult genus, particularly with regard to those species (3-5. 7) which are largely or entirely autogamous.

Literature: J. Holub, Preslia 42: 330-349 (1970). A. & C. Nieschalk, Abh. Ver. Naturk. Kassel 63: 1 -40 (1970). L. Reich- ling, Arch. Inst. G. -D. Luxemb. (Sei. Nat.) nov. ser., 22: 123-145 (1955). K. Senghas & H. Sundermann (edit.), Jahresb. Naturw. Ver. Wuppertal 23: 1 -132 (1970). D. P. Young, Watsonia 2: 253-276 (1952); 5: 127-139 (1962); Bot. Not. 1953: 253-270 (1953); Bull. Jard. Bot. Bruxelles 28: 123-127 (1958).

1 Rhizome long, creeping; hypochile with 2 erect lateral lobes, connected to epichile by a narrow joint 1. palustris

1 Rhizome short, horizontal or vertical; hypochile without lateral lobes, connected to epichile by 1 or more folds

2 Rhachis, pedicels and ovary densely pubescent

3 Leaves 4-10 cm, distichous; flowers deep purple 8. atrorubens

3 Leaves 1 -3 cm, spirally arranged; flowers greenish, with reddish tinge 9. microphylla

2 Rhachis, pedicels and ovary ± glabrous to scabridulous

4 Leaves distichous; rostellum absent, at least at maturity; flowers frequently cleistogamous or partially so

5 Flowers patent or obliquely pendent; hypochile purplish or pinkish inside (3—5). leptochila group

5 Flowers pendent; hypochile greenish-white inside 7. phyllanthes

4 Leaves spirally arranged; rostellum prominent and per­ sistent; flowers not cleistogamous

6 Leaves greyish or purplish; epichile at least as long as wide 6. purpurata

6 Leaves green; epichile not longer than wide 2. helleborine