Epidendreae

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 : 101

Tribe Epidendreae

Cremastra malipoensis G.W. Hu (2013: 64) , Zhou et al. (2016: 36). Type: — CHINA. Yunnan Province: Malipo County, Xiajinchang Village, 23°09´N, 104°51´E, alt. 1,300 m, under evergreen, broad-leaved forest, on a stony slope along stream, 4 March 2011, G.W. Hu HGW-00622 (holotype KUN, isotypes KUN, HNNU). ( Fig. 7 )

Ecology and phenology:—Terrestrial herb. Primary evergreen broad-leaved forests on rocky limestone at an elevations of 1000–1600 m a.s.l., commonly along streams. Very rare. Flowers in February–March.

Distribution:— VIETNAM, Ha Giang Province (Dong Van and Quan Ba districts). China (SE Yunnan).

Conservation status:—This species is a typical local endemic of the central part of the region recognized as a South-Chinese floristic province ( Averyanov et al. 2003). It is known for three very close locations near the border between Vietnam and China. The single known population in China is categorized under the ICUN criteria as Critically Endangered ( Hu et al. 2013). In Vietnam, the species also has the same status following the next Red List IUCN (2022) conditions: observed population reduction for 10 years or 3 generations ≥ 80% are not reversible (A2), based on direct observation (a), observed decline of the area of occupancy, extent of occurrence and habitat quality (b), and actual levels of exploitation (c); the area of occurrence <100 km ² (B1) and the area of occupancy <10 km ² (B2), with 3 known highly fragmented populations (a) and continuing observed decline of extent of occurrence (bi); the area of occupancy (bii); area, quality of habitat (biii); the number of mature individuals (bv); the number of mature individuals <250, observed, estimated or projected continuing decline in 25% in 3 years or 1 generation (C1) and observed, estimated, projected or inferred continuing decline when the number of mature individuals in each subpopulation (C2(i)) ≤ 50. Following presently available data, the conservation status of this species may be estimated as globally Critically Endangered, CR A2a-c; B1+ 2a,b(i-iii,v); C1+2(i).

Notes:—This is an extremely rare species in rich primary limestone forests. It probably stands, in all its former areas, on the verge of full extinction.

Studied specimen:— VIETNAM, Ha Giang Province, Quan Ba District, Cao Ma Po commune, Va Thang 2 village, lat. & long. 0430534X 2553087Y, elevation of 1620 m a.s.l., heavily disturbed primary limestone forest along a stream, terrestrial herb in a wet place, 50 cm tall; yellow flowers with purple-black spots, very rare; less than 10 individuals, 16 March 2018, Pham Van The, Trinh Ngoc Bon, Dinh Thi Kim Van, Dao Cong Anh, TB029 (photo LE01073002 http://en.herbariumle.ru/?t=occ&id=14200) . VIETNAM, Ha Giang Province, Dong Van District, Van Chai Commune , evergreen broad-leaved forests at an elevation of about 1000 m a.s.l., 22.02.202 0, Nguyen Phong, Nguyen Hoang Tuan, s.n. (photo LE01073006 http://en.herbariumle.ru/?t=occ&id=14204) .

Figures

FIGURE 7. Cremastra malipoensis G.W.Hu. A, B. Flowering plant in nature (specimen 16.03.2018, Pham Van The, s.n.). C, D. Intact apical part of inflorescence. E. Intact flowers, frontal view. F. Flattened leaves. G. Floral bracts Abaxial and adaxial sides. H. Flattened separate flowers, side view. I. Flattened sepals and petals. J. Flattened lip, view from different sides. K. Apical part of the lip, adaxial surface. L. Column, view from different sides. M. Pollinarium. N. Ovary, side view. O. Ovary, cross section (specimen 22.2.2020, P. Nguyen, T.H. Nguyen, s.n.). Photos were made by V.T. Pham (A, B) and T.H. Nguyen (C–O), with photo correction and design by T.H. Nguyen, L. Averyanov, and T. Maisak.