Aspidistra longzhouensis C. R. Lin, T. Meng & Yan Liu, 2023

Meng, Tao, Lu, Mao-Xin, Huang, Xue-Yu, Lin, Chun-Rui & Liu, Yan, 2023, Aspidistra longzhouensis (Asparagaceae), a new species from limestone areas in Guangxi, China, Phytotaxa 630 (1), pp. 80-86 : 81-85

Aspidistra longzhouensis C. R. Lin, T. Meng & Yan Liu , sp. nov. ( Fig. 1 )

Type:— China. Guangxi, Longzhou County, Shanglong Town, Longgang National Natural Reserve , limestone mountains, rare, 106.97° E, 22.42° N, elev. 140 m, 25 April 2021, Chunrui Lin & Tao Meng 1377 (holotype: IBK, isotype: IBK).

Diagnosis:— The new species resembles A. patentiloba and A. luodianensis in floral morphology, but clearly distinguished by its smaller leaf being 21–28 × 4.5–7.5 cm, flower completely pure white, stigma upper surface glabrous and with 4 radial, bifurcate lines at center.

Herbs perennial, evergreen, rhizomatous. Rhizome creeping, subterete, 6–8 mm thick, covered with scales; nodes dense. Roots numerous. Sheathing leaves 4–5, pale green, 1–7 cm long, enveloping the base of the petiole, becoming brown when dry. Leaves solitary, 1–1.5 cm apart; petiole stiffly upright, 22–48 cm long, 2–3 mm thick, adaxially sulcate; blade long elliptic, 21–28 cm long, 4.5–7.5 cm wide, green, frequently with small yellowish white spots, its base broadly cuneate to cuneate, inequilateral, long acuminate at apex, with entire margin, mid vein strongly prominent on abaxial surface, secondary veins prominent, 5–6 each side. Peduncle decumbent or declining, 2.5–6 cm long, with 5–7 bracts; bracts gradually wider from base to apex of peduncle, the most basal bract of the perianth broadly ovate, 12–14 mm long, 6–9 cm wide, pale green, with acuminate apex. Flowers solitary; perianth fleshy, completely pure white outside and inside; lobes 8 (occasionally 10), spreading, subequal, narrowly lanceolate, acuminate, 30–35 mm long, 3–5 mm wide at base, each lobe basally with an adaxial appendage; appendages oblong, 3–5 mm long, they explanate protruding horizontally over the tube opening and reducing the opening to ca. 2 mm; tube campanulate, 15–18 mm long, 13–15 mm in diameter. Stamens 8 (10), opposite to lobes, subsessile, inserted in the lower part of the perianth tube; anther yellow, ovoid, 2–3 mm long, 1–1.5 mm wide, apex of anther acuminate and distally reaching or just below level of stigma. Pistil white, 7–8 mm long; ovary indistinct; style cylindrical, 1–2 mm long, 2–3 mm in diameter; stigma dilated and bowl-like, 10–13 mm in diameter, 5–6 mm long, its upper surface glabrous, the central part slightly concave and with 4 radial, bifurcate lines, slightly 16 (20)-lobed at margin, abaxially longitudinally 16 (20)-ridged. Berry subglobose, dark brown at maturity, surface densely irregular tuberculate.

Phenology:— The new species was observed flowering from April to May, and fruiting to mature in March to April next year.

Etymology:— The specific epithet ‘ longzhouensis ’ is derived from the name of the type locality, Longzhou County, Guangxi, China. The Chinese name is given as ‘ ̎"Dz̊ŝā ’(Chinese pinyin: lóng zhōu zhī zhū bào dàn).

Distribution and ecology:— The new species is currently known only from the Longgang National Natural Reserve, Longzhou County in southwestern Guangxi, China. There it was found growing at elevation 140 m in the remnant primary evergreen broad-leaved forest on limestone mountains. Living plants introduced from the type locality are currently cultivated in Guilin Botanical Garden of Guangxi Institute of Botany.

Conservation status: — Aspidistra longzhouensis was only found from the type locality with two populations with about 400 individuals. All discovered individuals were occurring in Longgang National Nature Reserve, where the habitat was in good condition. The further detailed investigation of the same habitats is also needed to give a better understanding of its natural distribution and abundance. Thus, following the IUCN Red List Categories and Criteria ( IUCN 2022), it is provisionally assessed as Data Deficient (DD).

Taxonomic relationships:— Aspidistra longzhouensis is most similar to A. patentiloba Y. Wan & X. H. Lu in Wan (1989: 97, Fig. 2 ) in floral morphology, but differs by the leaf blade being 21–28 × 4.5–7.5 cm (vs. 28–57 × 6.3–13 cm), perianth lobes being white (vs. light purple) outside and white (vs. light yellow) inside, stigma upper surface of stigma with 4 radial lines, bifurcate lines (vs. 4–5 radial, red ridge) at center. The new species also close to A. luodianensis D.D. Tao in Tao (1992: 121, Fig. 3 ) in floral morphology, but differs by the leaf blade narrowly elliptic (vs. lanceolate), base cuneate (vs. attenuate), 21–28 cm (vs. 78–110 cm) long, perianth lobes being white (vs. reddishpurple) outside, perianth tube 13–15 mm (vs. 20–25 mm) in diameter, stigma upper surface of sigma with 4 radial, bifurcate lines (vs. 4–6 angle red star shaped) at center. A detailed comparison of the three species is presented in Table 1 .

Additional specimens examined (paratype):— CHINA. Guangxi Zhuang Autonomous Region: Guilin City, Botany Garden of Guilin , cultivation, 05 April 2017, Chun-Rui Lin 1060 ( IBK00455417 ) ; Longzhou county, Xiangshui Town , limestone mountains, 107.03°E, 22.42°N, alt. 150 m, 15 November 2022, Xue-Yu Huang, Wen-Jin Yang & Huan Chai ZYB03445 ( IBK00455435 ) ; Longzhou county, Shanglong Town , limestone mountains, 106.97° E, 22.42° N, alt. 140 m, 28 November 2022, Xue-Yu Huang, Wen-Jin Yang & Huan Chai ZYB03773 ( IBK00455456 ) .

Figures

FIGURE 1. Aspidistra longzhouensis: (A) plant habit; (B) fruiting plant; (C) flowers; (D–E) young berry; (F) flower side view; (G) perianth dissected opened to show stamens and pistil; (H) stigma upper view; (I) pistil side view.

FIGURE 2. Aspidistra patentiloba: (A) flower, apical view; (B) flower, with half of the perianth removed to show pistil; (C–D) flowers; (E) flowering plant; (F) flower, side view; (G) perianth dissected opened to show stamens and pistil; (H) pistil side view; (I–J) stigma, upper view; (K) stigma, lower view.

FIGURE 3. Aspidistra luodianensis: (A) habit; (B) flowers; (C) fruit; (D) flower, apical view; (E) flower, side view; (F) perianth dissected opened to show stamens and pistil; (G–I) stigma, upper view; (J) pistil side view; (K) plant.