Tên Khoa học: Aspidistra nutans Aver. & Tillich
Tên tiếng Anh:
Tên tiếng Việt: Tỏi đá trần
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Type: 10 Nov 2015, L. Averyanov, CPC 7158a, b/13279 (holotype: LE). Type prepared from cultivated plant col-lected in northwestern Vietnam (Son La province, Van Ho district, Tan Xuan municipality, Cot Moc village, territory of Xuan Nha natural reserve, eastern slopes of Pha Luong Mountain, remnants of primary and secondary broad-leaved evergreen humid forest on very steep mountain slopes com-posed by shale and sandstone at ca 1000 m a.s.l. around point 20°40′33.3′′N, 104°39′00.3′′E, 15 Nov 2013, L. Averyanov, N. T. Hiep, N. S. Khang, N. D. Hang, L. D. Qui, CPC 7158).

Etymology

The species epithet refers to the nodding fl owers placed on the bent down, hook-like peduncle apex.

Description

 Terrestrial perennial herb with underground or semi-epigeous simple or few branching, plagiotropic rhizome. Rhizome thick, stout, (4)5 - 8(12) cm long, (0.8)1.0 - 1.5(1.7) cm in diameter, densely covered by cataphyll bases. Leafy shoot at apex of rhizome, erect, very short, simple, 0.5 - 1.0 cm tall, enveloped by cataphylls. Cataphylls narrowly tubular, when flattened triangular, oblong or linear-lanceolate, (1.5)2.0 - 16.0(18.0) cm long, (4)8 - 15(20) mm wide, obtuse, erect and straight, when young dark violet to almost black, herbaceous or coriaceous, later light brownish to dull purple-brown, papyraceous, eventually disintegrated into long, dull light brown fibrous remains. Leaf on individual shoot 1(2), erect, (0.6)0.9 - 1.2(1.5) m tall, long petiolate. Petiole stiff , straight erect, dark dull green, (45)50 - 70(90) cm long, (2.5)3.0 - 8.0(9.0) mm in diameter, adaxially shallowly channeled. Leaf blade leathery, oblique to arching, narrowly elliptic, slightly pleated, tapering at base, shortly attenuate into an acute apex, (25)30 - 45(50) cm long, (4.5)5.0 - 7.5(8.0) cm wide, straight along margin, uniformly grass-green on both sides, with prominent median and secondary veins. Flowers 1 - 3(5), solitary, arising from apical part of rhizome at the base of the leafy shoot, pedunculate, odorless, (2.0)2.2 - 3.0(3.2) cm across, campanulate, often opening underground or semi-underground, forming an underground or semi-underground cavity by spreading perigone lobes of opening flower. Peduncle ascending to erect, hook-like curved near apex, facing flower down, dark dirty purplish-brown, in apical part sparsely speckled with dull greenish-white, (0.8)1.0 - 3.5(4.5) cm long, (1.5)2.0 - 3.0(4.0) mm in diameter, with (3)4 - 5(6) distant sterile bracts; bracts broadly triangular to broadly ovate, concave, thin, dull greenish finely densely speckled with dirty purple-brownish, papyraceous, obtuse, (4)5 - 10(12) mm long, (3.5)4.0 - 10.0(12.0) mm wide (being flattened), the two distal bracts close to each other and to flower base, often splitting at apex. Perigone campanulate, with rather spreading lobes, dull purplish-brown on both sides, fleshy, rather smooth, (1.2)1.3 - 1.5(1.6) mm long, (2.0)2.2 - 3.0(3.2) mm wide, with 8 free lobes. Perigone lobes subequal, fleshy, rather smooth, triangular narrowly ovate, almost fl at, straight and spreading, (7)8 - 11(12) mm long, (3.8)4.0 - 5.5(6.0) mm wide, blunt or roundish at apex. Stamens 8, subsessile, inserted at base of tube close to ovary; anthers ovoid to bean-shaped, (1.6)1.8 - 2.0(2.2) mm long, (0.9)1.0 - 1.1(1.2) mm wide, facing into the cavity formed by the base of the perianth tube and the adaxial surface of the stigma; pollen sacsintrorse; pollen light yellow. Pistil pure white; style fleshy, cylindrical, slightly broadening towards base and apex, (2.8)3.0 - 3.5(4.0) mm tall, 2.0 - 2.2 mm in diameter; stigma fleshy, hemispheric, (4.5)5.0 - 7.0(7.5) mm tall, (10)11 - 12(14) mm in diameter, circular in outline, densely adpressed to the perianth tube, straight along mar-gin, but slightly notched at verge opposite sepal bases, glabrous and glossy. Ovary inconspicuous, indistinct, greenish. Fruits unknown.

Distribution

Vietnam province: Son La (Van Ho district, Pha Luong Mountains). Endemic.

Habitat, phenology and conservation status

Terrestrial herb with underground plagiotropic rhizome.

Growing in primary and secondary submontane broad-leaved evergreen forests on shale and sandstone, commonly on shady very steep slopes, 900 - 1100 m a.s.l. Flowers in cultivation in September - November. Not common. Estimated

IUCN Red List status: ‘Data Deficient’ (DD).