Disporum dushanense B.Wang, Z.H.Wang & Q.W.Sun, 2021

Wang, Bo, Wang, Ze-Huan, Chen, Chun-Ling, Xu, Wen-Fen & Sun, Qing-Wen, 2021, Disporum dushanense (Colchicaceae), a new species from Guizhou, China, Phytotaxa 528 (2), pp. 144-148 : 144-147

Disporum dushanense B.Wang, Z.H.Wang & Q.W.Sun , sp. nov. ( Figs. 1 , 2 )

Type:— CHINA. Guizhou Province: Dushan County, Jiading Township, Zilin Mountain , 25°55′54″ N, 107°40′45″ E, elev. ca. 1250 m, 5 Apr 2020, Bo Wang, wb-202004003 (holotype: GZTM ; isotype: GZTM) .

The new species is similar to Disporum xilingense and D. acuminatissimum , but it differs from the former in leaf blade, purple-red (vs. greenish) flowers, purple-red (vs. white) stamens and filaments, and it differs from the latter in widely open purple-red flowers (vs. semi-opening and white) and purple-red (vs. white) stamens and filaments ( Table1 ).

Perennial, evergreen herbs with ca. 5 mm rhizomes, often 2–3 erect stems protruding. Stems erect, rarely branched, 30–60 cm tall, glabrous. Leaves 5–6, concentrated in distal third of stems, alternate; petioles 2–4 mm long; leaf blades ovate to elliptic, 6.5–9.1 × 3.4–3.8 cm, base broadly cuneate or subrounded and slightly conduplicate, margin entire or undulate, apex acuminate, or cuspidate, glabrous; 9–11-nerved, cross veins distinct. Inflorescence terminal, non-pedunculate, 1–3 (rarely 5)-flowered; pedicels 2.0– 2.5 cm long; flowers widely opening, almost flat, nodding, tepals pink-purple, narrowly lanceolate, 42–51 × 4–6 mm, base 1.0– 1.3 cm long saccate, densely pubescent or papillate on the inner surface and margin, apex long acuminate, veins distinct; stamens pink-purple, shorter than tepals, inserted at the base of tepals, 22–25 mm long; filaments, 18–22 mm long, base densely pubescent or papillate; anthers extrose, 6–7 mm long; pistil pink-purple, longer than stamens and shorter than tepals; styles and stigma together 24–26 mm long, stigmas trifid. Fruit a globose berry, purple black.

Distribution and ecology:— Known only from the type locality in the Zilin Mountain at ca. 1250 m. It is rare in the type locality, where fewer than 40 individuals were found. This population grows in a moist gully under the canopy of a broad-leaved forest dominated by Rhododendron sp. (Ericaceae) and Chimonobambusa sp. (Poaceae) , and accompanied by Arisaema lobatum Engl. (Araceae) , Polystichum longipaleatum Christ (Dryopteridaceae) , Monachosorum henryi Christ (Dennstaedtiaceae) , Asteropyrum cavaleriei (Lévl. et Vant.) Drumm. ex Hutch. (Ranunculaceae) , Athyrium sp. (Athyriaceae) , Elatostema sp. (Urticaceae) etc.

Etymology:— Derived from the type locality, Dushan (Guizhou, China). The Chinese name is D山万寿".

Phenology:— Flowering April–May; fruiting September–October.

Figures

FIGURE 1. Disporum dushanense. A. Habit (flowering branch). B., C. Tepal. D. Pistil. E. Stamen. (Drawing by Xiang Lu from the holotype)

FIGURE 2. Disporum dushanense. A. Habitat. B.–D. Flower. E., F. Floral. G. Lamina, upper surface. H. Lamina, lower surface. (Photographs by Bo Wang)