Weizhia pentaphylla G. Y. Li, Z. H. Chen, K. W. Jiang & B. Pan

Jiang, Kai-Wen, Chen, Yue, Li, Hua-Dong, Ma, Dan-Dan, Pan, Bo, Song, Zhu-Qiu, Wan, Kai-Yuan, Chen, Zheng-Hai & Li, Gen-You, 2023, Weizhia (Fabaceae: Phaseoleae), a new endemic genus from East China supported by morphological and molecular evidence, Phytotaxa 603 (3), pp. 235-248 : 240-243

Weizhia pentaphylla G. Y. Li, Z. H. Chen, K. W. Jiang & B. Pan bis, gen. & sp. nov.

( Figs. 3 and 4 ). Iẽk r yuè dòu téng l

Type: CHINA. Zhejiang: Shengzhou, Shantouding , on the S slope, under the forest, moist place, alt. ca. 60 m, 3 October 2021 (fl. with young fruits), Y. Chen ZY08 (holotype: NPH001335!; isotype: NPH001336!) .

Generic-specific description: —Perennial twining climbers, herbaceous, wholly pubescent with spreading hairs except for the corolla and pod, ca. 1.5 m long, the overground part deciduous in winter. Roots woody, thick. Stems slender. Leaves pinnate, leaflets (3–)5(–7); stipules lanceolate, 2–2.5 mm, basifixed, persistent or caducous; petiole 3–7 cm; rachis between two pairs of lateral leaflets 2–4 cm, that of terminal leaflet 0.5–1.5 cm; stipels awl-shaped, 1–2 mm, persistent; petiolules blackish-brown, 1–2 mm; leaflets thinly chartaceous, terminal leaflet 2.5–5.6 × 1.4–5.3 cm, rhomboid-ovate to ovate, acuminate to acute at apex, broadly cuneate, rounded to truncate at base, mid-vein and lateral veins slightly prominent on the adaxial surface, lateral veins 4–5 pairs; lateral leaflets slightly oblique, 1.4–5.3 × 1.1–4.5 cm. Pseudoraceme axillary, 0.4–10 cm, occasionally branched at base, slightly to strongly nodose with 2–5 flowers per node; bract 1, awl-shaped, minute, borne at base of pedicels. Pedicels 2–4 mm, 5–6 mm when fruiting; bracteoles 2, resembling bracts, borne at base of calyx. Calyx shortly tubular, 5-lobed, purple, ca. 6 mm, the lowest lobe longest, broadly triangular, ca. 1.3 × 1.1 mm, lateral lobes broadly deltoid, ca. 1 × 1.3 mm, the upper two 0.6 × 2.1 mm, slightly connate, emarginate at apex. Corolla grayish-green initially, turns white with violet petal-tips when mature; standard sub-elliptic, blade ca. 27 × 13 mm, with a basal claw ca. 3.5 mm, and two auricles at the connecting point of the blade and the claw; wing petals sub-oblong, blade ca. 10 × 3.5 mm, basal claw ca. 4 mm, the side opposite the claw with a spur ca. 1 mm long; keel petals slightly falcate, blade ca. 10 × 4.5 mm, basal claw ca. 5 mm, auricle minute, ca. 0.5 mm. Stamens 10; filaments ca. 15 mm, the free part upcurved, glabrous; anther uniform, basifixed. Pistil ca. 14 mm; ovary slender, light green, ca. 9 mm; style upcurved, white, ca. 5 mm; stigma capitate. Pods linear-oblong, sometimes slightly curved, 3.6–7.7 cm, compressed, sparsely hairy when young, glabrescent, slightly turgid between the seeds, valves turn greyish-brown when mature, twisted along both sutures when dehiscent. Seeds ellipsoid, ca. 7 × 4 mm, black with light yellow-brown speckles, smooth, slightly glossy.

Additional specimens examined (paratypes):— CHINA. Zhejiang: Shengzhou, Shengzhou Development Committee, Qianyuan Village , 2 October 2020, G. Y. Li, H. D. Li & Z. H. Chen SZ20100201 ( ZM). Forest Park of Mt. Chenghuangshan , under the forest, roadside, alt. 60 m, 23 June 2021, Z. H. Chen, L. Chen, G. K. Chen & G. Y. Li SZ21062301 ( ZM) . ibid., under the sparse forest, near the walking trails, alt. 58 m, 12 October 2021, G. Y. Li, Z. H. Chen & D. D. Ma SZ21101201 ( ZM) . ibid., alt. 60 m, 12 October 2021, G. Y. Li, Z. H. Chen & D. D. Ma SZ21101202 ( ZM) . ibid., on the S slope, under the forest, moist place, alt. ca. 60 m, 21 August 2021, K. W. Jiang, Y. Chen & H. D. Li ZY01 ( NPH) .

Distribution: — Weizhia pentaphylla is currently only known from its type locality in Shengzhou City, Zhejiang Province, E China ( Fig. 5 ).

Habitat: — Weizhia pentaphylla grows in shady and moist slopes under forest at an elevation from 60 to 100 m above sea level.

Phenology: —Flowering usually in October, fruiting from October to November.

Etymology: —The generic name, Weizhia , is in honor of Prof. Zhi Wei (1929–), a Chinese taxonomist at Zhejiang Museum of Natural History (ZM), who made outstanding contributions to the taxonomy of Chinese legumes. The epithet pentaphylla refers to the usually 5-foliolate pinnate leaves of the new species.

The Chinese name of Weizhia pentaphylla is proposed here as Iẽk: I refers to the name of an ancient State (IOi, Yue Guo) in Zhejiang Province; ẽ means pea in Chinese; k means vines or lianas, referring to the climbing habit of the species.

Conservation status: —In the type locality of Weizhia pentaphylla , only two populations with less than 20 individuals were discovered by the current authors, in which one population is located close to a residential area and is frequently disturbed by human activity. According to IUCN Standards and Petitions Subcommittee (2022), here we considered this species as Critically Endangered (CR-D). Conservation work for this species is urgently needed. The ex situ conservation efforts are currently underway at Ningbo Botanical Garden and Jiyang College of Zhejiang A & F University.

Figures

FIGURE 3. Weizhia pentaphylla G. Y. Li, Z. H. Chen, K. W. Jiang & B. Pan bis. A & B. Habit (B shows the occasional 7-foliolate pinnate leaves); C. Stipules; D. Leaf, showing the adaxial surface; E. Leaf, showing the abaxial surface; F. Leaf with 3 leaflets; G. Flowers; H. Flowers with young pods; I. Unmature pods; J.Anatomy of flowers, mature pods and seeds: (a) Flower; (b) Calyx; (c) Standard; (d) Wing petals; (e) Keel petals; (f) Pistil; (g) Stamens; (h) Mature and dehiscent pod; (i) Seeds.A–I by Hua-Dong Li, J (a–g) by Dan-Dan Ma, J (h & f) by Kai-Wen Jiang.

FIGURE 4. Weizhia pentaphylla G. Y. Li, Z. H. Chen, K. W. Jiang & B. Pan bis, gen. & sp. nov. A. Flowering and Fruiting branch; B. Stipules; C. Stipels; D. Calyx; E. Standard; F. Wing petal; G. Keel petal; H. Pistil; I. Stamens; J. Seed. Illustration by Bo-Heng Li.

FIGURE 5. Distribution map of Weizhia pentaphylla G. Y. Li, Z. H. Chen, K. W. Jiang & B. Pan bis in Zhejiang Province (red star). The map was drawn using the software ArcMap 10.5.