Description from
Flora of China
Amesia A. Nelson & J. F. Macbride; Arthrochilium (Irmisch) Beck (1890), not Arthrochilus F. Mueller (1858); Calliphyllon Bubani; Epipactis [unranked] Arthrochilium Irmisch; Helleborine Miller; Limonias Ehrhart; Parapactis W. Zimmermann.
Herbs, terrestrial, autotrophic or rarely holomycotrophic, medium-sized. Rhizome creeping, short or elongate, with many elongate, fleshy roots. Stem erect, leafy, with 2 or 3 scalelike sheaths toward base, glabrous or pubescent. Leaves 3 to many, cauline, spirally arranged, broadly elliptic to linear-lanceolate, plicate, scabrous or smooth. Inflorescence terminal, racemose, often secund, few to many flowered; floral bracts usually foliaceous. Flowers spreading or nodding, resupinate or very rarely not resupinate, medium-sized. Sepals free, spreading or connivent, glabrous, puberulent, or pubescent. Petals similar to sepals but shorter; lip fleshy, not spurred, constricted near middle to form a distinct epichile and hypochile, and sometimes with a mesochile in between; hypochile cymbiform or saccate, sometimes containing lamellae; mesochile (when present) short or elongate, narrow; epichile spreading, usually hinged at its base, thickened or not, variable in shape, sometimes 3-lobed, sometimes with wartlike calli or keels. Column short, without a column foot; anther sessile; pollinia 4, granular-farinaceous, without caudicles; viscidium absent in autogamous species; rostellum usually large, very rarely absent; stigma rounded to subquadrate. Capsule pendulous or ascending, obovoid to ellipsoid.
About 20 species: throughout Europe and through temperate and alpine parts of E, S, and SW Asia, also in tropical Africa and North America; ten species (two endemic) in China.
(Authors: Chen Xinqi (陈心启 Chen Sing-chi), Luo Yibo (罗毅波); Phillip J. Cribb, Stephan W. Gale)