Hypericum shunhuangshanense J. W. Xiao, W. Q. Qin & W. X. Ouyang, 2025

Ou, Xi-Ya, Chu, Zhao-Fu, Ouyang, Wen-Xiang, Qin, Wei-Qiang, Quan, Zhi-Xin, Zhang, Meng-Hua, Zhang, Dai-Gui & Xiao, Jia-Wei, 2025, Hypericum shunhuangshanense (Hypericaceae), a new species from Hunan, China, PhytoKeys 260, pp. 13-23 : 13-23

Hypericum shunhuangshanense J. W. Xiao, W. Q. Qin & W. X. Ouyang sp. nov.

Figs 2 , 4

Type.

China • Hunan Province, Xinning County, Shaoyang, Shunhuang Mountain Nature Reserve , 1650 m alt., 26.4145, 110.9272, 13 August 2024, Jiawei Xiao, Wenxiang Ouyang and Zhixin Quan 240813001 (Holotype: Herbarium of Shaoyang University ( HSU); Isotype: JIU) .

Diagnosis.

Hypericum shunhuangshanense is similar to H. faberi , H. seniawinii and H. erectum , but differs from the latter three in the following aspects: its stems are curved or flat and swollen, leaves are decussate, inflorescence is cymose, sepals possess pellucid streaked laminar glands and black marginal glands, and anthers are darker in color.

Description.

Perennial herb, 0.1–0.3 m tall. Stems cylindrical, curved or creeping-ascending, usually branched; lower parts reddish-brown, upper parts green. Leaves sessile, 1.7–3.2 cm long, 1.0– 1.4 cm wide, oblong to oblong-linear, apex acute to rounded, usually with a small apical point; base cuneate to rounded, margin entire, flat or slightly dark-colored, green above, light green but not glaucous below. Veins: 2 pairs of main lateral veins, each arising from the lower part of the midrib, curving upward in an arc; sparse reticulate veins faintly visible below. Leaf marginal glands black, spaced, rather large. Inflorescence terminal, a capitate cyme with 3–5 flowers; pedicels 0.8–2.8 (– 5) cm long; bracts small, linear-lanceolate. Flowers 3.0– 6.5 cm in diameter. Sepals 5, oblong-lanceolate, 3–5 mm long, 1–2 mm wide, margin entire, midrib distinct, fine veins inconspicuous, laminar glands pellucid, streaks; marginal glands black. Petals golden to lemon yellow, without red tinge, spreading, triangular-obovate, 1.0– 1.5 cm long, 0.5–0.7 cm wide, margin entire, laminar glands pellucid, streaks; marginal glands black, few. Stamens in 3 fascicles, 15 stamens per fascicle, longest stamens 1.2–1.5 cm long, equal in length to several petals. Ovary ovoid to pyramidal or subglobose, 1.0– 1.5 mm long, 0.5–1.0 mm wide, 3 - loculed, with axillar placentation; styles 0.7–1.1 cm long, ca. twice as long as the ovary. Capsule broadly ovoid to narrowly ovoid or subglobose, 6–10 mm long, 4–7 mm wide. Seeds dark reddish-brown, cylindrical, ca. 2 mm long, with a narrow keel-shaped protrusion, surface with shallow linear-reticulate to linear-foveolate ornamentation.

Phenology.

Flowering from July to August; fruiting from August to September.

Conservation status.

During 2024, we conducted sampling of the Hypericum shunhuangshanense population and discovered one additional site near the original discovery location, each harbouring roughly 100 plants. The species primarily inhabits exposed rocky gullies from the mid-section to the summit of the mountain. Further fieldwork is needed to evaluate the exact distribution of the species and it is possible that other populations could be found in similar habitats of the Shunhuang Mountain Nature Reserve. Therefore, we temporarily assign the species to the category DD (Data Deficient) according to the International Union for Conservation of Nature ( IUCN 2022).

Distribution and ecology.

The species is known to be found in the Shunhuang Mountain Nature Reserve, Xinning County, Shaoyang, Hunan Province, 1650 m alt.

Etymology.

The species name “ shunhuangshanense ” refers to the origin of this type, Shunhuang Mountain Nature Reserve, Xinning County, Shaoyang City, Hunan Province.

Figures

Figure 2. Holotype of Hypericum shunhuangshanense J. W. Xiao, W. Q. Qin & W. X. Ouyang.

Figure 4. Hypericum shunhuangshanense. A, B. Habit; C. Flower; D. Leaves (decussate); E. Leaves; F. Sepals; G. Petals; H. Stamens; I. Pistils; J. Longitudinal section of fruit (a), cross-section of fruit (b).