Aspidistra bella Aver., Tillich & K.S. Nguyen, 2018

Averyanov, Leonid V., Hans. - Jürgen, Nguyen, Khang Sinh & Maisak, Tatiana V., 2018, Aspidistra bella (Asparagaceae), a new species from northern Vietnam, Phytotaxa 364 (2), pp. 205-208 : 205-207

Aspidistra bella Aver., Tillich & K.S. Nguyen sp. nov. ( Fig. 1 & 2 )

Type:— VIETNAM, Ha Giang province, Bac Me district, ex hort. on 10 March 2018, L. Averyanov, T. Maisak CPC 7484 / 14369 (holotype: LE 01042153, isotypes: LE 01042154, LE 01042155, LE 01042156).

Paratypes:— VIETNAM, Ha Giang province, Bac Me district, Thuong Tan municipality, primary broad-leaved humid evergreen forest on very steep slopes and along rocky ridge composed with solid crystalline highly eroded limestone at elevation 1200–1285 m around point 22°38’19.0’’N 105°17’06.5’’E, terrestrial herb on rocky slope, leaves uniformly dark green, fruits globular, about 1 cm in diam., densely haired with soft spine-like hairs, stalk 2.5–4 cm long, common, 16 November 2014, L. Averyanov, N. T. Hiep, N. S. Khang, T. Maisak, L. Osinovetz, CPC 7484 ( LE 01042157, LE 01042158).

Diagnosis:— Aspidistra bella differs from closest A. dolichanthera Chen (1982: 77) by the creeping rhizome; the almost naked peduncle 1.4–3.5 cm long and curved downward; the numerous flowers 5.5–7.5 mm in diameter, the triangular perigone lobes 4.5–6.5 mm long and the short anthers 3.8–4.6 mm long.

Etymology:— The species name refers to the attractive beautiful white flowers, clustering at the apex of individual shoots.

Description:— Terrestrial rhizomatous herb. Rhizome plagiotropic, creeping, terete, branching, (0.8)1–1.4(1.6) cm in diameter, densely nodal, distal part ascending to erect, terete, (3)4–6(7) cm long, (1)1.2–1.8(2) cm in diameter, simple, densely nodal, grassy green, with many cataphylls and 2–5(6) leaves; basal part with thick, distant, rigid, light grey, semiwoody, straight spreading roots distally richly branching. Cataphylls convolute, cuneate, acute, dark purple-brown and tubular when young, later light dull yellowish, almost flat, papyraceous, (1)2–8(10) cm long and (4)5–8(10) mm wide, splitting into irregular fibrous–papyraceous remains with age. Leaves petiolate, (0.5)0.6–0.9(1.2) m long. Petiole stiff, erect, straight, or slightly curved, (25)30–40(50) cm long. Leaf blade upright to somewhat arching, elliptic, attenuate at base and apex, (25)30– 45(50) cm long, (6)8–16(18) cm wide, plicate, uniformly grassy green above and below, with prominent midvein and several secondary veins well seen on both sides, arising from midvein in basal half of leaf blade. Flowers odorless, numerous, arising by (1)2–3(5) from each axil, nodding, pure milky-white, widely open, (1.3)1.5–1.8(2) cm in diameter. Peduncles appearing in groups, successively, one by one, dirty purple, finely streaked with white, (1.4)1.8–3(3.5) cm long, (1.6)1.8–2(2.2) mm in diameter, curved downward, with 4–6 sterile bracts. Peduncle bracts broadly ovate to reniform, concave, scarious, pure white or slightly tinged with violet, roundish at apex, (5)6–7(7.5) mm long and (6)7–11(12) mm wide (being flattened), upper three approximate near flower base. Perigone tube campanulate, (4)4.5–5.5(6) mm long, (5.5)6–7(7.5) mm wide, glossy. Perigone lobes (4)6(7), subequal, triangular broadly sagittate, (4.5)5–6(6.5) mm long, (4.5)5–8(8.5) mm wide, slightly convex, almost round at apex, fleshy, glossy, smooth, with irregularly recurved and often incised margin, at broadest part auriculate, narrowing adaxially into rather narrow rectangular base. Stamens (5)6(7), anthers brightly yellow, sessile, erect (parallel to style), arising near the base of the tube, narrowly ovoid, (3.8)4–4.4(4.6) mm long, (1)1.2–1.4(1.6) mm wide, with narrow connective, pollen sacs facing the style; pollen brightly yellow. Pistil cylindric, erect, (5.6)5.8–6.2(6.4) mm tall, slightly broadening at apex and base; ovary inconspicuous, white to white tinged with violet, (1)1.2–1.4(1.6) mm long and wide; style white, cylindrical, (4)4.2–4.4(4.6) mm long, (0.8)0.9–1(1.2) mm in diameter; stigma truncate, almost flat, pure white or white with very light indistinct violet irregular spots, subcircular to rounded triangular, sometimes with inconspicuous irregular lobes, (1)1.2–1.4(1.6) mm across, its upper surface smooth. Fruits greenish, globular, (0.7)0.8–1(1.1) cm long and wide, densely hairy with long soft spine like papillae, stalk (2.5)3–4(4.5) cm long.

Distribution:— Northern Vietnam (Ha Giang province, Bac Me district). Endemic.

Ecology:— Very steep rocky slopes and mountain summits covered by primary broad-leaved evergreen humid forests on marble-like, highly eroded limestone at elevations of 1200–1300 m a.s.l. Flowering in cultivation in March–April. The species is considered to be of “Least Concern” (LC) (IUCN 2012).

Taxonomic relationships:— Aspidistra bella belongs to a group of white or light yellowish-flowering species, which includes in Vietnam and allied countries species such as Aspidistra anomala Averyanov & Tillich (2016: 141) , A. brachystyla Averyanov & Tillich (2008: 37) , A. campanulata Tillich (2007: 337) and A. dolichanthera . Among the mentioned taxa, our species is most similar to A. dolichanthera , described in detail by Lang et al. (1999). From A. dolichanthera our plant well differs in long creeping rhizome (vs. short ascending rhizome), descending, curved downward, purplish peduncles 1.4–3.5 cm long, with only a few white, distant broadly ovate bracts 5–7.5 mm long, roundish at apex, leaving peduncle almost naked (vs. stiff erect, white peduncles 12–17 cm long, nearly completely covered by acute-lanceolate, brown bracts 3–3.5 cm long), perigone tubular campanulate, 4–6 mm long, 5.5–7.5 mm wide (vs. perigone tube widely campanulate to funnel shaped, 6–8 mm long, 8 mm wide), perigone lobes triangular, 4.5–6.5 mm long (vs. perigone lobes elongate, 10–12 mm long), anthers 3.8–4.6 mm long (vs. 5–6 mm long).

Figures

FIGURE 1. Aspidistra bella Aver., Tillich & K.S. Nguyen corresponding to Averyanov, T. Maisak CPC 7484 / 14369. VIETNAM, Ha Giang province, Bac Me district, plant flowered under cultivation on 10 March 2018. Photos, correction and design by L. Averyanov.

FIGURE 2. Aspidistra bella Aver., Tillich & K.S. Nguyen. Paratype and paratype specimen detail. Averyanov et al., CPC 7484 (LE01042158). Photos, correction and design by L. Averyanov.