Cymbidium macrorhizon Lindley (1833: 162)

Averyanov, Leonid V., Nguyen, Van Canh, Truong, Ba Vuong, Nguyen, Khang Sinh, Nguyen, Cuong Huu, Maisak, Tatiana V., Doan, Nga Thi, Nguyen, Tuan Hoang, Pham, Van The, Dat, Pham Thi Thanh, Thai, Tran Huy, Nguyen, Van Khuong & Trinh, Ngoc Bon, 2023, New orchids in the flora of Vietnam VI (Orchidaceae, tribes Arethuseae, Cymbidieae, Diurideae, Epidendreae, Vandeae, and Vanilleae), Phytotaxa 597 (2), pp. 87-110 : 96

Cymbidium macrorhizon Lindley (1833: 162) , Seidenfaden (1992: 344), Pearce & Cribb (2002: 270, fig. 60, pl. 9), Liu et al. (2006: 231), Puy & Cribb (2007: 323), Schuiteman et al. (2008: 279), Chen et al. (2009: 279), Rokaya et al. (2013: 523), Jalal & Jayanthi (2015: 18), Lin et al. (2016: 91), Zhou et al. (2016: 40), Ormerod et al. (2021: 85) . Type: —KASHMIR. Kashmir, icon. Role (holotype K000395362). ( Fig. 4 )

= Cymbidium sikkimense auct. non Hooker (1890: 9): Gagnep. in Gagnepain & Guillaumin (1934: 412 p. p.), Seidenfaden (1973: 116).

Ecology and phenology:—Achlorophyllous leafless terrestrial herb. Secondary coniferous forests and grassy woodlands derived from an old plantation of Pinus kesiya on granite at an elevations of 1300–1400 m a.s.l. Very rare. Flowers in April–May.

Distribution:— VIETNAM, Lam Dong Province (Dalat Town Area). Pakistan, Nepal, Bhutan, N India, Myanmar, Thailand, Laos, China, Korea, Japan.

Conservation status:—The only population of this species discovered in Vietnam occupies less than 500 m 2 of territory and according to the formal Red List IUCN (2022) criteria, it meets in Vietnam with the following conditions: extent of occurrence <100 km ² (B1) and the area of occupancy <10 km ² (B2) with one known location (a); the number of mature individuals <250 with an observed, estimated, projected, or inferred continuing (C2), when the number of mature individuals in the alone known population ≤ 50 (a (i)); the number of mature individuals <50 (D): nationally Critically Endangered CR B1(a)+2(a), C2a(i), D. At the same time, the discovery of this species in secondary plant communities reveals some potential ability of the species to survive in old pine plantations that are more or less stable in the highlands of southern Vietnam.

Notes:—All earlier records of this species for Phu Quoc Island treated in the past as a territory of Cambodia or Vietnam are based solely on one wrongly identified specimen (Ile de Phú Quốc, № 75, Contest-Lacour) housed in the P Herbarium (P00392341) and belonging in fact to C. finlaysonianum Lindley (1833: 164) . No more records of this remarkable, easily recognizable species in these countries were reported. In this regard, our discovery is the first to be supported by herbarium material.

Studied specimen:— VIETNAM, Lam Dong Province, Dalat Town area , secondary open grassy old coniferous forest and woodlands derived from old Pinus kesiya plantation at an elevation of 1300–1400 m a.s.l., erect terrestrial achlorophyllous aphyllous herb with inflorescences to 30 cm tall and thick rhizome to 25 cm long on a steep grassy slope, very rare, 31 May 2022, L. Averyanov, T. Maisak, Nguyen Van Khang, Truong Ba Vuong, Nguyen Huu Cuong, AL 1300 ( LE01168960 https://herbariumle.ru/?t=occ&id=140407, photos LE01123416 https://herbariumle.ru/?t=occ&id=137206, LE01123417 https://herbariumle.ru/?t=occ&id=137207.

Figures

FIGURE 4. Cymbidium macrorhizon Lindl. A. Flowering plants in nature. B. Intact inflorescence. C, D. Intact flowers, frontal and half-side views. E. Flattened flowering plants. F, G. Flattened rhizomes. H. Flattened floral parts. I. Intact column apex, anther cap, and lip epichile, frontal view. J. Intact lip, adaxial surface. K. Sagittal lip section. L–N. Column and anther cap, view from different sides. All photos were made from the plant used for the preparation of the specimen Averyanov et al., AL 1300, by L. Averyanov, with photo correction and design by L. Averyanov and T. Maisak.