Dumasia zhangjiajieensis Y. K. Yang, L. H. Liu & J. K. Wu (2004: 67)

Jiang, Kai-Wen, Corlett, Richard T., Tian, Bin & Pan, Bo, 2021, Taxonomic notes on the genus Dumasia (Fabaceae), Phytotaxa 522 (2), pp. 109-120 : 118-119

5. Dumasia zhangjiajieensis Y. K. Yang, L. H. Liu & J. K. Wu (2004: 67) . Fig. 5

Type:— CHINA. Hunan: Dayong County, Zhangjiajie , Luobota , in sylvis monti, alt. 680 m, 6 th July 1981. Lin-Han Liu 762254 (holotype HNNU) .

Dumasia wulingyuaniea Y. K. Yang, L. H. Liu & J. K. Wu (2004: 67) , nom. inval. pro syn.

Description: —Twining herbs, 2– 3 m. Stem slender, terete, multi-branched, sparsely pubescent when young, glabrescent. Leaves trifoliolate; stipules and stipels subulate to setaceous, 0.5–1.7 mm, persistent; petioles 3.4–5.2 cm; leaflets membranous to thin chartaceous, nearly glabrous on both surfaces, light green adaxially, glaucous abaxially, blunt and mucronate at apex, subrounded to broadly cuneate at base, secondary veins 4–6 pairs, reticulate veins obvious on both surfaces; terminal leaflet ovate, elliptic or ovate oblong, 2.5–4.8 × 1.8–3.7 cm; lateral ones smaller, oblique, 1.7–4 × 1–2.7 cm; petiolules 1–3 mm. Pseudoracemes axillary, 5.5–16 cm, with repand wings at base of peduncles, 9–16-flowered; wings 3.2–3.7 cm × 1–4 mm; bracts and bracteoles setaceous or subulate, 0.5–1.2 mm, minute. Calyx tubular, grass green, 5–7 × 3.5–4 mm, longitudinal veined, obliquely truncate at the calyx mouth, gibbose at the base. Corolla light yellow. Standard obovate, 18 × 8 mm, apex emarginate, auriculate, attenuate to a short claw at base; wing petals falcate, 15 × 2.5 mm, apex rounded, attenuate to a 10 mm claw; keels nearly subequal as the wing petals, with a 5.5 mm-blade and 11 mm-claw. Stamens 10, diadelphous, 15–17 mm. Ovary linear, with a slender stipe surrounded by a basal disc; style dilated at the bending part; stigma capitate and hairy. Pods moniliform, glabrous, acuminate at apex, attenuate at base, 4–5-seeded, conspicuously constricted between the seeds, valves thin leathery. Seeds subglobose and dorsoventrally compressed, ca. 6 × 6 × 3 mm, bluish black, hilum raised, ca. 3 mm long.

Distribution and habitat: — Dumasia zhangjiajieensis is currently known from the type locality, Hunan Province, and several other photo records from Luzhou, SE Sichuan Province (http://ppbc.iplant.cn/tu/4295622). More occurrences may lie between the two sites, which includes Chongqing, Guizhou, and Hubei. It grows on very shaded and moist slopes.

Phenology: —Flowering in May to July; fruiting from June to September.

Notes: — Dumasia zhangjiajieensis can be easily characterized by its winged peduncle, which is unique in the genus. It bears moniliform pods, which are similar to those of D. villosa DC. (1825: 97) but totally glabrous.

Iconography citation: — Yang et al. (2004: 74): figure 3.

Conservation status: — Dumasia zhangjiajieensis is poorly known and collected. The Zhangjiajie population has only ca. 30 mature individuals. According to IUCN Categories (2019), the species is considered as Data Deficient (DD). Additional field surveys and observations are needed.

Specimens examined:— CHINA. Hunan: Dayong County, Zhangjiajie, Zicaotan , alt. 500 m, 10 th September 1985, L. H . Liu 016895 ( HNNU). ibid., 24 th June 2002, L. H . Liu & G. W . Hu 23392 ( HNNU). ibid., 21 st September 2017, B . Pan 2737 ( HITBC) .

Figures

FIGURE 5. Dumasia zhangjiajieensis Y. K. Yang, L. H. Liu & J. K. Wu A. Vegetative branches, showing the adaxial surface of leaves; B. Abaxial surface of a leaf; C. Branches with immature fruits; D. The winged peduncles; E. Fruiting branches; F. Pods; G. Seeds. Scale bar = 1 cm. Photographs by Bo Pan.