Miguelia shenzhenica (Z.J.Liu & S.C.Chen) Aver., 2023

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 : 107

Miguelia shenzhenica (Z.J.Liu & S.C.Chen) Aver. , comb. nov. ( Fig. 10 )

≡ Vanilla shenzhenica Z.J.Liu & S.C.Chen (2007: 301) , Chen et al. (2009: 168), Barretto et al. (2011: 97), Zhou et al. (2016: 136).

Type: — CHINA. Guangdong: Shenzhen, Longgang , Meishajian , alt. 300 m, on tree trunk and rock along a valley, 22 February 2005, Z. J. Liu 3025 (holotype NOCC).

Ecology and phenology:—Creeping succulent herbaceous lithophytic or epiphytic vine. Primary and secondary lowland evergreen broad-leaved forests on shale and granite. Very rare. Flowers in March.

Distribution:— VIETNAM, Thua Thien Hue Province (Phu Loc and Nam Dong districts within the territory of Bach Ma National Park), Da Nang City Area (Ba Na Mountain). SE China.

Conservation status:—Only two locations of this easily recognizable species have been discovered in Vietnam untill now. They are located in the lowland areas of Bach Ma National Park and Ba Na–Nui Chua Nature Reserve in the central part of the country. Taking into consideration the high recreation pressure and vigorously increasing tourism activity in both areas, the species meets the following formal Red List IUCN (2022) criteria: observed population reduction for 10 years or 3 generation ≥ 80% are not reversible (A2), based on direct observation (a) and observed decline of the area of occupancy, extent of occurrence and habitat quality (c); the area of occurrence <100 km ² (B1) and the area of occupancy <10 km ² (B2), with 1 known population (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, and % of mature individuals in one subpopulation = 90–100% (C2(ii)); the number of mature individuals <50 (D). These conditions identify the species as nationally Critically Endangered, CR A2a,c; B1a,b(i-iii,v)+2a,b(i-iii,v); C1+2(i,ii); D1.

Notes:—This remarkable species is easily recognizable from other species of Miguelia Aver. (2011: 45) by its inflorescence, which regularly bears 4–5 simultaneously opening flowers distinctly larger than in other species of the genus. The plant has some interest in ornamental horticulture.

Studied specimen:— VIETNAM, Thua Thien Hue Province, Bach Ma Nation Park, 18 March 2021, Phạm Th ị Thanh D ạt s.n. ( LE01090412 https://en.herbariumle.ru/?t=occ&id=79882) . VIETNAM, Da Nang City Area, Ba Na - Nui Chua Nature Reserve, Ba Na Mountain , evergreen broad-leaved lowland forest on granite at anelevation of about 500 m a.s.l., common in the area, March 2021, Nguyen Van Canh, s.n .

Figures

FIGURE 10. Miguelia shenzhenica (Z.J.Liu & S.C.Chen) Aver. A. Flowering plant in nature. B, C. Intact inflorescences. D. Flattened flowering plant. E. Flattened inflorescence. F. Floral bract, side view. G. Flower, frontal view. H. Flattened sepals and petals. I. Lip, view from above. J. Lip epichile ornamentation. K. Pedicel, ovary and column, side view. L. Apical half of the column, side view. M. Column apex with intact anther cap, frontal view. All photos were made by P.T.T. Dat from the specimen, 18 March 2021, Pham Thi Thanh Dat s.n., with photo correction and design by L. Averyanov and T. Maisak.