Cheirostylis yunnanensis Rolfe

Bhattacharjee, Avishek, 2012, On the status of some species of Cheirostylis Blume (Orchidaceae) from India, Candollea 67 (1), pp. 31-35 : 34

Cheirostylis yunnanensis Rolfe in Bull. Misc. Inform. Kew 1896: 201. 1896.

Typus: CHINA. Yunnan: Mengtse , IV.1893, Hancock 25 (holo-: K, photo!) .

= Cheirostylis munnacampensis A. N. Rao in Nordic J. Bot. 8: 340. 1988 (synonymised by CHEN & al., 2009).

Typus: INDIA. Arunachal Pradesh: Munna Camp (W. Kameng Dist.), 2000 m, 16.V.1984, A. N. Rao 14567 (holo-: Orchid Herbarium Tipi!; iso-: Orchid HerbariumTipi!).

Distribution. – India: Arunachal Pradesh, Sikkim (fide PEARCE & CRIBB, 2002), West Bengal; China; Myanmar; Thailand; Vietnam.

Other specimens examined. – INDIA. Arunachal Pradesh: Tipi , 28.III.2002, A. N. Rao 30862 (Orchid Herbarium Tipi) . West Bengal: Darjeeling District, Mahananda Wildlife Sanctuary , 1 km away from Kalijhora towards Setikhola , 12.III. 2008, T. K. Paul 43698 ( CAL) .

Note. – While describing C. munnacampensis, RAO (1988) discriminated it from C. yunnanensis in having oblong petals, hypochile with 7 pairs of calli and stelids almost two times longer than the rostellar arms instead of spathulate petals, hypochilewith3or 4pairsof calli and stelids almost as long as the rostellar arms found in C. yunnanensis . But C. yunnanensis isahighlyvariablespecies and shows variation inthe shape of petals, number of calli inside the hypochile, relative length of stelids and rostellar arms. The shape of petals varies from obliquely oblong to spathulate to obliquely elliptic-lanceolate. SEIDENFADEN (1978) observed obtuse apices of the petals, whereas in the present study both obtuse and acute apices of petals have been found. During the present study 3-9 pairs of calli observed inside the hypochile of C. yunnanensis . Therelative lengthof stelids and rostellar armsalso varies in different specimens of C. yunnanensis , but the stelids are always longer than the rostellar arms. Considering these ranges of variation ( Fig. 2 ), C. munnacampensis is confirmed as a heterotypic synonym of C. yunnanensis .

Figures

Fig. 2. – ‘Cheirostylis munnacampensis A. N. Rao’. A. Flower; B. Petal; C. Labellum; D. Column with anther-cap – Cheirostylis yunnanensis Rolfe; E. Flower; F-G. Petal; H. Labellum (partly fragmented); I. Portion of hypochile with appendages (magnified); J. Column. [A-D: after RO, 1988; E-J: T. K. Paul 43698, CAL, dissected from dry and pressed specimen]