Neottia Guett., Hist. Acad. Roy. Sci. Mém. Math. Phys. (Amsterdam) 1750: 374 (1754).
Ophris Mill., Gard. Dict. Abr. ed. 4 (1754), nom. illeg.
Nidus-avis Ortega, Tab. Bot.: 24 (1773).
Cardiophyllum Ehrh., Beitr. Naturk. 4: 148 (1789).
Diphryllum Raf., Med. Repos. 5: 357 (1808).
Listera R.Br. in W.T.Aiton, Hortus Kew. 5: 201 (1813), nom. cons.
Neottidium Schltdl., Fl. Berol. 1: 454 (1823).
Distomaea Spenn., Fl. Friburg. 1: 245 (1825).
Pollinirhiza Dulac, Fl. Hautes-Pyrénées: 120 (1867).
Nidus Riv. ex Kuntze, Revis. Gen. Pl. 2: 674 (1891).
Bifolium Nieuwl., Amer. Midl. Naturalist 3: 128 (1913), nom. illeg.
Holopogon Kom. & Nevski in V.L.Komarov (ed.), Fl. URSS 4: 750 (1935).
Archineottia S.C.Chen, Acta Phytotax. Sin. 17(2): 12 (1979).
Diplandrorchis S.C.Chen, Acta Phytotax. Sin. 17(1): 2 (1979).
Herbs, small, terrestrial, autotrophic or holomycotrophic. Rhizome short, with many densely crowded, tufted, fibrous or fleshy, sometimes coralloid roots. Stem erect, with several sheathing bracts at base, green, buff, or reddish brown, with or without green leaves. Leaves (when present) 2 very rarely 3 or 4 in Neottia ovata (Linnaeus) Bluff & Fingerhuth], opposite or subopposite, usually borne midway along stem, sessile or subsessile, green, sometimes with white venation, ovate, deltoid-ovate, ovate-cordate, or cordate, base shallowly cordate, truncate, or broadly cuneate. Inflorescence terminal, racemose and many flowered or rarely reducedto a solitary flower; peduncle glabrous or pubescent; floral bracts persistent, usually shorter than ovary, membranous. Flowers small, resupinate or very rarely not resupinate, membranous or fleshy, green, purple, yellowish brown, or reddish; pedicel slender; ovary ellipsoid. Sepals free, similar, spreading. Petals often narrower and shorter than sepals; lip usually much larger than sepals and petals, sometimes with a pair of auricles at base, without a spur but sometimes shallowly concave at base, apex deeply 2-lobed or emarginate, or rarely unlobed; disk sometimes with a glandular pubescent longitudinal strip or a shallow glossy depression. Column suberect, straight or slightly arcuate, long or short, without a foot; anther inserted at rear margin of clinandrium, erect or slightly nodding; filament extremely short and inconspicuous; pollinia 2, each ± longitudinally 2-parted, granular-farinaceous, without caudicles; stigma subterminal, concave or protruding; rostellum spreading horizontally or suberect, ligulate or ovate, large. Capsule small.
Temp. & Subarctic Northern Hemisphere to NW. Africa

Neottia nidus-avis (L.) Rich.  Europe to Caucasus, NW. Africa.

World Checklist of Selected Plant Families.The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; accessed 04/07/2020
Bibliography and References:
Bedoschi G. 1987 Neottia nidus-avis (L). Orchis no.50. 186-187 (1987)
Dickerson B. 1983 Birds nest orchid ( Neottia nidus-avis) survey in Waresley Wood. Ann. Rep. Huntingdon. Fauna Flora Soc. 35. 28-30 (1982 publ. 1983)
Dressler RL. 1990 The Neottieae in orchid classification. Lindleyana. 5. 102-9.
Roberts J. 1993 British native orchids. Orchid Rev. 101. (1189): 15-16 (1993)
Rysy W. 2002 Neottia nidus-avis (L.) L.C. Rich.: Vogelnestwurz als Orchidee des Jahres 2002. Orchidee 53. (2): 168-169 (2002)