Roots when present fleshy, villose; when absent replaced by internodal rhizoids. Rhizome terete to moniliform, of few to many equal internodes. Stem terete to moniliform, abbreviated to elongate, with a few scattered to subrosulate leaves. Leaves sometimes withered at anthesis, with a short-petiolate base dilating into a tubular amplexicaul sheath; lamina obliquely oblong to suborbicular, various shades of green, sometimes with a median white-silver band, rarely marmorate. Inflorescence pubescent; peduncle abbreviated to elongate, with a few congested to scattered sheathing bracts; rachis abbreviated to elongate; floral bracts equal in length to pedicel plus ovary. Flowers resupinate, glabrous to pubescent on the outer surfaces of the sepals. Dorsal sepal free or connate to nearly its entire length with the lateral sepals, when free forming a hood with the petals. Lateral sepals connate to nearly entire length along lower and upper margins, enclosing base to all of the labellum. Petals obliquely linear-oblong to spathulate, upper margin usually agglutinate to dorsal sepal, lower margin sometimes adnate to lateral sepals. Labellum fused to half of the lower column margins; hypochile shallowly saccate, containing two to many often seriate, dentiform to subulate appendages on each side; mesochile abbreviated to elongate, semi-tubular; epichile entire to bilobed, lobules entire to lacerate. Column with or without a short semiterete base, slightly dilated; anther ovoid to ovoid-lanciform, biloculate; pollinia attenuated basally and attached to an oblong to linear-ligulate viscidium; rostellum deltoid, the remnant deeply bifid; stigma lobes separate, placed laterally near apical corners of column at base of rostellum; stylidia or sterile extensions of stigma lobes parallel to and equalling the rostellum, dentiform to linear-spathulate. Ovary cylindric-fusiform to obconical, glabrous to pubescent, twisted. Capsule fusiformellipsoid to obconical; pedicels rarely elongating. (PO, PC).
About 50 species occur in tropical and South Africa, Madagascar, the Comoro Islands, the Mascarenes, Sri Lanka, India, Bhutan, China, Taiwan, Burma (Myanmar), Thailand, Vietnam, Japan, the Philippines, Malaysia, Indonesia, Caroline Islands, Papua New Guinea, Australia, Vanuatu, and New Caledonia. (PO, PC).
Cheirostylis plants grow as forest floor terrestrials, on humus or among mosses in depressions on bare and mossy rocks and on old walls or as epiphytes on mossy tree branches. They occur in lowland forests and coastal areas, but more often the plants inhabit montane forests up to 2500 m. The leaves of some taxa with fleshy moniliform rhizomes wither at flowering, after which these plants become dormant for a while. (PO, PC)
Lawler (1984) reported that C. lepida Rolfe has been used medicinally in Nigeria. (AP)
Plants should be grown in shallow pots in soil or on rocks with a some moss to prevent desiccation. Deciduous species may require a rest period when they are not watered, but the rhizome should be kept moist to prevent dehydration. (PO, PC)
Little is known about the pollination of most Cheirostylis species except for a few autogamous taxa. Jones (1997) believed that the Australian C. notialis D.L.Jones is self-pollinating because of a non-functional viscidium (which forms the median lobe of the rostellum). Teratological forms of the Mascarene C. nuda (Thouars) Ormerod also appear to be autogamous because the ovaries are swollen prior to anthesis. Other teratological entities such as C. takeoi (Hayata) Schltr. from the southern Ryukyu Islands and Taiwan and C derchiensis Ying also seem to be autogamous. (PO, PC)
Cheirostylis is an easily recognized genus because of its fleshy, moniliform rhizome with internodal rhizoids (instead of nodal roots), flowers with obconical ovaries, connate sepals, a lip containing parallel seriate appendages, and a column with two separate stigma lobes that bear sterile extensions or stylidia. It is not possible, however, to exclude from Cheirostylis those species lacking one or more of the diagnostic generic characters described above. For example, C. inabai Hayata from Taiwan has a cylindric- fusiform ovary but otherwise fits in the genus quite well. Its close relative, C. octodentata Ames from the Philippines, has a similar ovary and a terete rhizome that roots at the nodes as well.
Other species may combine the features of a terete rhizome rooting at the nodes, flowers with a cylindric-fusiform ovary, and free sepals but possess a typical Cheirostylis column and lip structure. These divergent taxa are usually assigned to Zeuxine Lindl., but flowers of that genus never have a column with sterile extensions of the stigma lobes. Gymnochilus Blume is based on two teratological taxa from Madagascar and the Mascarenes. The columns of both have aborted stylidia and presumably a nonfunctional rostellum. Study of the available material and comparison with the similar Cheirostylis gymnochiloides (Ridl.) Rchb.f. indicates that Gymnochilus belongs in Cheirostylis. Arisanorchis Hayata was originally described as leafless, differing from Cheirostylis in having an entire lip lacking subdivisions or calli. Masamune (1968) reported that it has leaves withering at anthesis. Arisanorchis represents, without doubt, a peloric Cheirostylis. (PO, PC).