Lysimachia porcatisepala S. R. Yi, 2020

Yi, Sirong, 2020, Lysimachia porcatisepala, a new species of Lysimachia (Primulaceae) from Chongqing, China, Phytotaxa 434 (1), pp. 118-122 : 118-119

Lysimachia porcatisepala S. R. Yi , sp. nov. ( Figs. 1 & 2 )

Diagnosis:—This species is similar to L. huangsangensis J. J. Zhou, X. L. Yu & Y. F. Deng in Zhou et al. (2015: 3) in calyx lobes abaxially crested, but differ by its stems, leaves and calyx sparsely white pubescent (not glabrous), inflorescence corymose (not raceme), and the corolla1.7–2.0 cm long (not 1.0– 1.2 cm long).

Type:— CHINA. Chongqing: Wanzhou Qu, Lishu Zhen, Tanzhangxia , 108°48′04″E, 30°40′05″N, 395 m a.s.l., under damp forest in valley, 15 May 2019, S. R. Yi 8189 (holotype, KUN; isotyepes, KUN, PE) .

Description:—Perennial herbs, stems erect, 20–40 cm tall. Stems light purple, unbranched, sparsely white pubescent. Leaves opposite, 2–3 pairs; petiole 0.8–2.0 cm long, light purple, sparsely white pubescent, concave above, circular; blades ovate, narrowly ovate lanceolate to lanceolate, 1.5–5.5 cm long, 1–3 cm broad, dark green above, light purple beneath, glabrous except for sparsely white pubescent on the margin, apex acute, margin entire, base broadly wedgeshaped, decurrent onto the petiole becoming extremely narrow wings middle and lateral veins concave above and convex beneath, lateral veins 3–5 pairs beneath. Inflorescence of 2–10-flowered umbels borne on the leaf axil. Pedicels erect, 1.0– 1.8 cm long, light purple, sparsely white pubescent. Bracts leaf-like, lanceolate to narrowly lanceolate, 2–2.5 cm long, 1–1.2 cm broad, pubescent outside, base attenuate and decurrent onto the petiole, petioles 1–1.3 cm long. Calyx green, white pubescent outside, glabrous inside, 5-lobed almost to base, lobes linear lanceolate, 0.9–1.1 cm long, 1.2–1.3 mm broad, sparsely white pubescent with densely light purple markings outside, lobes apex caudate, margin membranous, crested outside. Corolla yellow, 1.7–2.0 cm long, basal tube 4.0– 4.4 mm long, 5-lobed, lobes narrowly ovate, 1.3–1.5 cm long, 5.8–6.2 mm broad, apex obtuse, margin entire. Stamens 5, yellow, basal conjoined tube 3.8–4.2 mm long, filaments unequal, shorter ones 2.5–3.0 mm long, longer 5.0– 5.5 mm long; anthers yellow, broadly ovate to oblong, connectives 2.3–2.5 mm long, 1.1--1.3 mm wide, T-shaped, opening by lateral splits. Ovary ovoid, 1.5–1.8 mm high, 1.1–1.3 mm in diam., sparsely white pubescent; style rodlike, 7.5–7.8 mm long, light purple below, green-white upward, stigma capitate, purple. Capsules unseen.

Distribution and habitat: — Lysimachia porcatisepala was found only in Tanzhangxia, Lishu Zhen, Wanzhou Qu, Chongqing City, China. It grows under damp forest in the valley at the elevation of 360– 400 m. It is considered as Critically Endangered (CR) according to current information and the IUCN Red List criteria ( IUCN, 2012) for it is only found in the area of less than 1 km 2 in Tanzhangxia according to the current investigation results.

Phenology: —Flowering from April to May.

Note: ―Based on field observations during 2016–2019, it is found that flowering plants of Lysimachia porcatisepala was withered before fruiting. This species has underground repent stems/rhizomes, so it is deserved to further study for breeding strategies. According to the classification of morphologically ( Chen and Hu 1979, Chen et al. 1989), the new species belongs to Ser. Drymarifoliae Handel-Mazzetti (1928: 96) and similar to L. huangsangensis J. J. Zhou, X. L. Yu & Y. F. Deng in Zhou et al. (2015: 3) in calyx lobes abaxially crested, but differs in its stems erect and sparsely white pubescent, leaves ovate, narrowly ovate lanceolate to lanceolate, margin sparsely white pubescent, inflorescence corymose 2–10-flowered, pedicels sparsely white pubescent, calyx lobes linear lanceolate, very sparse white pubescent and dense light purple markings outside, glabrous inside, corolla 1.7–2.0 cm long, tube 4.0– 4.4 mm long, corolla lobes narrowly ovate, 1.3–1.5 cm long, 5.8–6.2 mm wide, apex obtuse, ovary sparsely white pubescent ( Table 1).

Figures

FIGURE 1. Lysimachia porcatisepala S. R. Yi. A. Habit. B. Flower bud. C. Leaf blade. D. Bract. E. Calyx lobes. F. Corolla opened. G. Stamen. H. Pistil.

FIGURE 2. Lysimachia porcatisepala S. R. Yi.A. Habit. B. Inflorescence (adaxially). C. Inflorescence (abaxially). D. Corolla. E. Corolla opened. F. Flower bud. G. Leaf blade. H. Bract. I. Pistil. J. Calyx lobes. K. Stamen.