Flora of China
  FOC Vol.25 (2009)              | Family List  Orchidaceae  PDF Amitostigma  PDF   | Link Font:+ Big | - Small
   36. Amitostigma  Schlechter Repert. Spec. Nov. Regni Veg. Beih. 4: 91. 1919.
无柱兰属   wu zhu lan shu
Authors:Authors: Xinqi Chen, Stephan W. Gale & Phillip J. Cribb

Mitostigma Blume, Mus. Bot. 2: 189. 1856, not Decaisne (1844).


Herbs, terrestrial, slender. Tubers subglobose to ovoid, undivided, fleshy, neck with several slender roots. Stem erect, 1- or occasionally 2-leaved, glabrous or occasionally pubescent. Leaves basal or cauline, usually green and unspotted, rarely with purple-brown blotches, oblong, lanceolate, elliptic, or ovate, base contracted into amplexicaul sheath. Inflorescence a terminal raceme, glabrous; peduncle elongate, with 1 or more sterile bracts; rachis 1- to several flowered. Flowers often secund, resupinate, white, pink, mauve, or purple, rarely yellow; ovary usually straight, twisted, shortly pedicellate, cylindric-fusiform, glabrous. Sepals free, oblong to ovate, 1-veined. Petals free, often connivent with dorsal sepal and forming a hood, usually wider than sepals; lip spreading, spurred at base, 3-lobed; disk often papillose; mid-lobe often divided, forming 2 lobules; spur cylindric to narrowly conic, short to elongate. Column very short; anther usually erect, oblong-ellipsoid to obovoid, 2-locular, locules parallel or slightly divergent; pollinia 2, oblong, sectile, granular-farinaceous; caudicles straplike; viscidia naked, oblong-ovate; rostellum rather small, 3-lobed, base with ± ascending arms on both sides, margin adnate to column; stigma ventral, 3-lobed, lobes confluent, relatively large, flat to somewhat raised; auricles 2, large, stout, placed laterally at base of anther. Capsule suberect.

About 30 species: E Asia and adjacent areas; 22 species (21 endemic) in China.

The generic affinity of several of the entities presently referred to Amitostigma remains questionable and in need of re-examination; many of the endemic Chinese taxa are poorly known.

The generic affinity of several of the entities presently referred to Amitostigma remains questionable and in need of re-examination; many of the endemic Chinese taxa are poorly known.

1Plants 2-leaved (A. alpestre rarely 1-leaved)(2)
+Plants 1-leaved(7)
2(1)Leaves cauline, widely spaced(3)
+Leaves basal, subopposite(4)
3(2)Lip obovate, 3-lobed near middle, 4.5-5.5 mm wide, longer than broad; lateral lobes ovate-oblong, ca. 0.5 mm wide; spur 4-4.5 mm.17  A. alpestre    台湾无柱兰
+Lip orbicular to transversely elliptic, 3-lobed toward apex, ca. 8.5 mm wide, broader than long; lateral lobes quadrate, ca. 2.5 mm wide; spur 5-7 mm.18  A. yuanum    齿片无柱兰
4(2)Rachis 1-flowered.19  A. papilionaceum    蝶花无柱兰
+Rachis 3- to more than 10-flowered(5)
5(4)Leaves usually appressed to substratum; petals ca. 5 × 3 mm; lip ca. 9 mm.22  A. physoceras    球距无柱兰
+Leaves erect to porrect; petals 3-3.5 × 1.5-2 mm; lip 4.5-6 mm(6)
6(5)Lip 3-lobed below middle; lateral lobes linear.20  A. bifoliatum    棒距无柱兰
+Lip 3-lobed above middle; lateral lobes ovate.21  A. wenshanense    文山无柱兰
7(1)Leaf appressed to substratum, adaxially with purplish brown blotches.1  A. hemipilioides    卵叶无柱兰
+Leaf erect or porrect, uniformly green(8)
8(7)Rachis 1- or rarely 2-flowered(9)
+Rachis usually 3- or more flowered (A. faberi rarely 1- or 2-flowered)(15)
9(8)Spur 8-17 mm, ca. as long as to exceeding ovary(10)
+Spur 2-4 mm, usually much shorter than ovary(12)
10(9)Lip 3-lobed toward apex, 11-15 × 13-19 mm; lateral lobes broadly oblong-ovate, ca. 5 mm wide.6  A. pinguicula    大花无柱兰
+Lip 3-lobed below middle, 8-10 × 6-10 mm; lateral lobes linear-oblong or ovate-triangular, 1-3 mm wide(11)
11(10)Dorsal sepal 4-5 mm; spur 11-12 mm.7  A. dolichocentrum    长距无柱兰
+Dorsal sepal ca. 7 mm; spur 8-9 mm.8  A. tibeticum    西藏无柱兰
12(9)Stem densely pubescent around leaf base; floral bract much shorter than ovary; lip 5-6 mm.2  A. amplexifolium    抱茎叶无柱兰
+Stem glabrous; floral bract nearly as long as to exceeding ovary; lip 7-15 mm(13)
13(12)Flower yellow.3  A. simplex    黄花无柱兰
+Flower pale purple, pink, or white(14)
14(13)Leaf 0.1-0.4 cm wide; petals broadly ovate, 4.5-5.5 mm wide.4  A. farreri    长苞无柱兰
+Leaf 0.6-1 cm wide; petals ovate, 1.6-2 mm wide.5  A. monanthum    一花无柱兰
15(8)Mid-lobe of lip 4-7 mm wide, nearly as broad as to broader than long(16)
+Mid-lobe of lip 0.5-3.5 mm wide, much longer than broad(18)
16(15)Ovary and pedicel 15-25 mm; dorsal sepal ca. 7 mm; lip ca. 13 mm.16  A. gonggashanicum    贡嗄无柱兰
+Ovary and pedicel 6-10 mm; dorsal sepal 2.5-3.5 mm; lip 5-7.5 mm(17)
17(16)Peduncle ebracteate; spur 2-3 mm.14  A. basifoliatum    四裂无柱兰
+Peduncle with 1 sterile bract; spur 5-6 mm.15  A. faberi    峨眉无柱兰
18(15)Mid-lobe of lip ca. 3.5 mm wide, deeply divided above middle to form 2 distinct lobules.9  A. parceflorum    少花无柱兰
+Mid-lobe of lip 0.5-2 mm wide, apex truncate, obtuse-rounded, occasionally emarginate or shallowly notched(19)
19(18)Lateral lobes of lip oblong-obovate, 1.6-2 mm wide; spur 3.5-6 mm.10  A. tetralobum    滇蜀无柱兰
+Lateral lobes of lip lanceolate, linear-oblong, ovate-oblong, or triangular, 0.3-0.8 mm wide; spur 1-2.5(-3.5) mm(20)
20(19)Peduncle ebracteate; flowers white; mid-lobe of lip ca. 1.6 mm.11  A. capitatum    头序无柱兰
+Peduncle with 1 or 2 sterile bracts; flowers pink, rose-pink, purplish red, or purple; mid-lobe of lip 2-4 mm(21)
21(20)Plants 7-25 cm tall; leaf usually basal; lip 3-lobed above middle.12  A. gracile    无柱兰
+Plants 24-36 cm tall; leaf cauline; lip 3-lobed below middle.13  A. trifurcatum    三叉无柱兰
   List of lower taxa