栏目

曲茎石斛Dendrobium flexicaule Z. H. Tsi

曲茎石斛Dendrobium flexicaule Z. H. Tsi

别名:曲茎石槲;曲轴石斛;

科名:兰科 Orchidaceae

属名:石斛属 Dendrobium

《中国植物志》第19卷119页
  45. 曲茎石斛(植物研究)图版18:4-6
  Dendrobium flexicaule Z. H. Tsi, S. C. Sun et L. G. Xu in Bull. Bot. Res. 6 (2): 113-116 (fig.). 1986.
  茎圆柱形,稍回折状弯曲,长6-11厘米,粗2-3毫米,不分枝,具数节,节间长1-1.5厘米,干后淡棕黄色。叶2-4枚,二列,互生于茎的上部,近革质,长圆状披针形,长约3厘米,宽7-10毫米,先端钝并且稍钩转,基部下延为抱茎的鞘;花序从落了叶的老茎上部发出,具1-2朵花;花序柄长1-2厘米,粗约1毫米,基部被3-4枚长2-4毫米的膜质鞘;花苞片浅白色,卵状三角形,长约3毫米,先端急尖;花梗和子房黄绿色带淡紫,长3-4.5厘米;花开展,中萼片背面黄绿色,上端稍带淡紫色,长圆形,长28毫米,中部宽8毫米,先端钝,具5条脉;侧萼片背面黄绿色,上端边缘稍带淡紫色,斜卵状披针形,与中萼片等长而较宽,先端钝,具5条脉,萼囊黄绿色,圆锥形,长约8毫米,宽10毫米,末端近圆形;花瓣下部黄绿色,上部近淡紫色,椭圆形,长约25毫米,中部宽13毫米,先端钝,具5条脉;唇瓣淡黄色,先端边缘淡紫色,中部以下边缘紫色,宽卵形,不明显3裂,长17毫米,宽14毫米,先端锐尖,基部楔形,上面密布短绒毛,唇盘中部前方有1个大的紫色扇形斑块,其后有1个黄色的马鞍形胼胝体;蕊柱黄绿色,长约3毫米;蕊柱足长约10毫米,中部具2个圆形紫色斑块并且疏生上部紫色而下部黄绿色的叉状毛,末端紫色、与唇瓣结合而形成强烈增厚的关节;蕊柱齿2个,三角形,基部外侧紫色;药帽乳白色,近菱形,长约2.5毫米,基部前缘具不整齐的细齿,顶端深2裂,裂片尖齿状。花期5月。
  产河南(地点不详)、湖北(神农架地区)、湖南东部(衡山南岳)、四川南部(甘洛)。生于海拔1200-2000米的山谷岩石上。模式标本采自四川(甘洛)。

《Flora of China》 Vol. 25 (2009)
Dendrobium flexicaule  Z. H. Tsi S. C. Sun & L. G. Xu, Bull. Bot. Res., Harbin. 6(2): 113. 1986.
曲茎石斛   qu jing shi hu
?Dendrobium henanense J. L. Lu & L. X. Gao.
Stems cylindric, slightly upcurved, 6-11 cm, 2-3 mm in diam., unbranched, with several nodes, internodes 1-1.5 cm, pale brownish yellow when dry. Leaves 2-4, alternate on upper part of stem, oblong-lanceolate, ca. 3 × 0.7-1(or more) cm, subleathery, base decurrent into clasping sheaths, apex obtuse and slightly hooked. Inflorescences on old stems after leaves have fallen, 1- or 2-flowered; peduncle 1-2 cm, ca. 1 mm in diam.; basal sheaths 3 or 4, 2-4 mm, membranous; floral bracts pale white, ovate-triangular, ca. 3 mm, apex acute. Pedicel and ovary yellowish green, tinged with pale purple, 3-4.5 cm. Flowers spreading; dorsal sepal yellowish green abaxially, upper part slightly tinged with pale purple; lateral sepals yellowish green, upper distal margins tinged with pale purple, mentum yellowish green; petals: lower part yellowish green, upper part pale purple; lip pale yellow, front margin pale purple, margin purple below middle, disk with a large purple flabellate blotch at middle front part, callus yellow; column yellowish green, stelidia purple at base on outside, foot with 2 rounded purple spots, lower part yellowish green, apex purple, anther cap creamy white. Dorsal sepal oblong, ca. 28 mm, ca. 8 mm wide at middle, 5-veined, apex obtuse; lateral sepals obliquely ovate-lanceolate, ca. as long as dorsal sepal and broader, 5-veined, obtuse; mentum conic, ca. 8 × 10 mm, nearly rounded. Petals elliptic, ca. 25 mm, ca. 13 mm wide at middle, 5-veined, apex obtuse; lip broadly ovate, ca. 17 × 14 mm, adaxially densely pubescent, rear part with a saddle-shaped callus, base cuneate, margin inconspicuously 3-lobed, apex acute. Column ca. 3 mm, foot ca. 10 mm, sparsely covered with bifid hairs, upper part of hairs purple; column teeth 2, deltoid; anther cap subrhombic, ca. 2.5 mm, basal front margin with irregular teeth, apex deeply bilobed, lobes sharply toothed.
● Lithophytic on rocks in mountain valleys; 1200-2000 m. Henan, Hubei (Shennongjia), E Hunan (Heng Shan), SC Sichuan (Ganluo).

TOP