Aspidistra triradiata N.Vislobokov, 2015

Vislobokov, Nikolay A., 2015, Two new species of Aspidistra (Asparagaceae, Nolinoideae) from northern Vietnam: A. clausa and A. triradiata, Phytotaxa 207 (3), pp. 265-272 : 269-270

Aspidistra triradiata N.Vislobokov sp.nov. ( Fig. 2 )

Similar to A. hainanensis , but flowers larger (1.8–2.4 cm long, Ø 1.8 –2.8 cm vs. 1–1.2 cm long, Ø 1.3 –1.5 cm), perigone urceolate, lobes with 4 verrucose keels, stigma with three purple radial lines. Type: — VIETNAM, Vinh Phuc province, Tam Dao district, Tam Dao National Park, about 6 km NW from Tam Dao City. 21° 29,942’ N, 105˚ 36,973’ E, alt. 1208 m, rainforest, 19 November 2014, N.A. Vislobokov 14098 (holotype, MW!), including reproductive organs in liquid collection at Moscow University.

Herbaceous perennial, rhizomatous, evergreen plant. Rhizome creeping, with very short internodes, epigeous, Ø 8.6 – 9.0 [8.8] mm. Roots grey, Ø 2.4 mm, with 2–3-layered velamen and dense hairs persistent up to root base, endoderm 2–3-layered, pericycle of cells with not lignified walls. Rhizomes with regularly repeating units, each comprising distichously arranged phylloms: 4–8 cataphylls followed by 3–5 foliage leaves. Cataphylls oblong, 8.5–16.5 [12.5] cm long, 9 mm wide. Foliage leaves not divided into petiole and lamina, leaf gradually narrowing to base. Leaf base dark to light green, adaxially sulcate, 2.7–5.2 [3.9] mm wide. Leaf blade dark to light green, linear, distally narrowly acuminate, 56–82.5 [73.3] cm long, 1.2–2 [1.6] cm wide, with 1–2 secondary veins at both sides of the midvein. The midvein prominent at lower surface and the secondary veins somewhat prominent at upper surface. Peduncle (specialized reproductive shoot) pale green with purple spots, 0.7–3.7 [2.1] cm long, Ø 2.3 –3.5 [3] mm, with 3–5 widely ovate, 7.5–10.1 [8.5] mm long, 5.6–6.5 [6.1] mm wide distichously arranged scale leaves. Flower solitary at the end of a peduncle. Perigone urceolate, 18.2–23.9 [20.4] mm long, Ø 17.5 –28.1 [23.1] mm; tube white with purple spots to completely purple outside, purple and verrucose inside, 15.6–18.6 [14.6] mm long, Ø 14.2 –19.8 [17.1] mm; lobes 6(–7), purple spotted to completely purple at both sides, verrucose at upper side, triangular-ovate, obtuse, 7.6–10.5 [9.3] mm long, 3.9–8.3 [5.6] mm wide, lobes basally with 4 prominent verrucose longitudinal keels, 2 median keels extending down inside perigone, each lateral keel fusing with adjacent one. Stamens 6(–7), in the same number as perigone lobes, inserted at the bottom of the perigone tube, at the radii of tepals; anthers sessile, 2.5–2.8 [2.7] mm long, 2.4 mm wide, introrse. Pistil table-shaped, 6.5–8.8 [7.9] mm high ( Fig. 2g ). Style white, 3.1–3.5 [3.3] mm long, Ø 1.9 –2.9 [2.5] mm. Stigma white with three purple radial lines and purple edge at the upper side, white at lower side, disc-shaped, papillose at the upper surface, slightly convex, Ø 11.7 –15 [13.2] mm. Ovary inconspicuous, superior, 3- locular. Fruits are unknown.

Molecular description: — Differences found in alignments of all currently available accessions of Aspidistra of investigated sequences of psb A- trn H and 5S-NTS regions are summarised in Tables 1–2. In psb A- trn H region ( Table 1), the new species A. triradiata is similar to A. clausa and Aspidistra sp. 1 . In 5S-NTS region, the most remarkable feature of the new species is a large insertion represented by nucleotides 53–125 (direct nucleotide positions; these are equivalent to positions 57–129 in the alignment, Table 2). In addition, the following features distinguish 5S-NTS sequences of the new species from other accessions (in all cases, direct nucleotide positions): Thymine not Cytosine at position 24; Thymine insertion at position 44; Cytosine not Guanine at position 205 (within indel 8); Cytosine not Guanine/Thymine at position 283; Guanine not Adenine at position 311; Adenine not Cytosine at position 444.

Additional specimen examined (paratype): — VIETNAM, Vinh Phuc province, Tam Dao district, Tam Dao National Park, about 6 km NW from Tam Dao City. 21° 29,942’ N, 105˚ 36,973’ E, alt. 1208 m, rainforest, 24 November 2014, N.A. Vislobokov 14111a-e (MW!).

Etymology: — The specific epithet refers to the color pattern of stigma which includes three radial bright purple lines.

Distribution: — The species is known only from the type locality.

Taxonomic relationships:—The new species resembles and closely relates to the A. hainanensis complex mentioned by Tillich & Averyanov (2012). The complex includes SE Asian Aspidistra species with oblanceolate to lineate, tufted leaves and trimerous flowers, e.g. A. caespitosa Pei (1939: 101) ,. A. larutensis De Wilde & Vogel (2005: 126) , A. linearifolia Wan & Huang (1987: 220) , A. lingchuanensis Lin & Guo in Guo et al. (2015: 86), A. minutiflora Stapf (1903: 113) , A. yingjiangensis Peng (1989: 173) . However, A. triradiata shows a number of peculiar characterstates, i.e. clearly urceolate perigone tube, 4 verrucose keels, verrucose adaxial surfaces of tepals and tube, and peculiar color patterns of perigone and stigma.

Figures

FIGURE 2. Aspidistra triradiata. a, b. flowers, top view; c, d. stigma, top view (c) and view from below (d); e, f. longitudinal section of flower; g. pistil, side view, perigone removed; h. flower, side view; i, j. flowers on rhizome of flowering plant; k. rhizome with bases of leaves, leaves removed; l. flowering plant.