Sedum anminanum Q. L. Gan, Z. Yu Li & Xin W. Li 2026, sp. nov.

Sedum anminanum Q. L. Gan, Z. Yu Li & Xin W. Li sp. nov. Figs 1, 2 Diagnosis. Sedum anminanum is most similar to S. stellariifolium Franch. in having dense glandular hairs on the plant, alternate leaves, and yellow petals, but the new species can be easily distinguished from S. stellariifolium by its perennial habit (vs. annual or biennial), soft stems (vs. woody at base), basal branches with rooted nodes (vs. without basal branches and rooted nodes), obovate-spatulate leaf blades (vs. rhombic-ovate to broadly rhombic-ovate), red-brown anthers (vs. yellow), and persistent styles divergent outward (vs. incurved). (see Table 1). * Based on several years of field observations, this species produces leafy branches from the base of the flowering stems (Fig. 1 D). These branches are rooted at their bases and continue to grow and overwinter after the flowering stems have set fruit and withered (Fig. 1 C); in the following year, they develop into more flowering stems bearing similar branches, and this cycle repeats year after year. Therefore, this species is undoubtedly a perennial herb capable of clonal growth. Type. China • Hubei Province: Zhuxi County, Eping Township, Jiepaigou Village, in dry crevices of exposed rocks on the sunny mountain slope, 32°10'04.12"N, 109°35'09.62"E, alt. 604 m, 24 July 2013, Q. L. Gan 3401 (holotype, PE!; isotype HIB!). Description. Perennial fleshy herbs. Stems, leaves and inflorescences densely glandular-pubescent, hairs white, spreading and sticky. Roots fibrous, at basal nodes of stems. Stems caespitose, many-branched from base, straight or distally tortuous, 10–15 cm tall, 1.5–2.5 mm in diameter, soft, greenish to reddish. Leaves alternate, both surfaces densely glandular-pubescent; blades obovate-spatulate, 6–12 × 4–8 mm, apex minutely blunt, margin entire, base cuneate to narrowly cuneate, decurrent into petiole; adaxially mid-green, abaxially greenish; midrib inconspicuous, not convex abaxially; petiole 4–8 mm, adaxial compressed, abaxial rounded, spurless at base. Cymes arising from most leaf axils, lax, 3 - to many-flowered, usually with few leaf-like bracts below, peduncles 5–15 mm, distal cymes usually arranged in terminal corymbiform clusters; flower buds ovoid. Flowers 5 - merous, bisexual; pedicel 5–10 mm, densely glandular-pubescent; sepals five, narrowly triangular, 1.5–2 mm, apex obtuse, margin entire, base spurless, mid-green, glandular-pubescent outside, glabrous inside; petals five, yellow, lanceolate, 3.5–4.5 mm long, ca. 1.2 mm wide, margin entire, acute at apex, shortly connate at base, glandular-pubescent outside, glabrous inside; stamens 10, in two whorls, glabrous; antespalous ones 3–3.5 mm long, antepetalous ones 2.5–3 mm long, inserted ca. 0.6 mm from petal base; filaments yellow; anthers globose, ca. 1 mm in diameter, red-brown; nectar scales orange, broadly fan-shaped, 0.4–0.5 mm long, 0.5–0.7 mm wide, apex erose; carpels five, erect, green; ovary oblong-lanceolate, 3–3.8 mm long, sparsely glandular-pubescent, styles subulate, ca. 1.5 mm, glabrous. Follicles five, erect, oblong-lanceolate, 3.2–4 mm long, ca. 1.5 mm wide, connate ca. 0.5 mm at base, adaxially not gibbous, glandular-pubescent or almost glabrate at maturity, brownish; persistent styles divergent outward. Seeds numerous, brown, obovate-oblong, 0.3–0.4 mm long, minutely papillate. Phenology. Flowering from June to August, fruiting from August to September. Distribution and habitat. Sedum anminanum, a new endemic species of the karst region in the heart of Dabashan (Daba Mts.), central China, is known only from two adjacent villages, Jiepaigou and Hongyan, on the border between Zhuxi County in Hubei Province and Zhenping County in Shaanxi Province. It grows in crevices of exposed rocks on sunny cliffs of dolostone mountains, at an elevation of ca. 550–650 m. The accompanying species are mainly perennial herbs, including succulent plants such as Sinocrassula indica var. viridiflora K. T. Fu and Sedum dielsii Hamet, and ferns such as Pteris actiniopteroides Christ, P. vittata L., Aleuritopteris argentea var. obscura (Christ) Ching, and Hypodematium crenatum (Forssk.) Kuhn. Some shrubs and other herbs also grow on the rock slopes near the cliffs, such as Celtis biondii Pamp., Quercus baronii Skan, Pittosporum illicioides Makino, Paliurus hemsleyanus Rehd., Rhamnus utilis var. hypochrysa (Schneid.) Rehd., Rostrinucula sinensis (Hemsl.) C. Y. Wu, Miscanthus floridulus (Labill.) Warb. and Silene fortunei Vis. Etymology. The specific epithet is named in honor of Professor An-Min Lu (1939 –), a taxonomist at the Institute of Botany, Chinese Academy of Sciences, who has devoted over 60 years to studies on the phylogeny and evolution of angiosperms and taxonomic studies of Juglandaceae, Solanaceae, and Cucurbitaceae in China. Vernacular name. An Min Jing Tian (Chinese). Additional specimens examined (paratypes). China - Hubei • Q. L. Gan 3399 & 3400 (HIB!); Zhuxi County, Eping Township, Jiepaigou Village; 24 Jul. 2013 • Q. L. Gan KUN 1300 (KUN!); same locality; 4 Aug. 2018 - Shaanxi • Q. L. Gan 26601, 26602 & 26603 (PE!); Zhenping County, Hongyan Village; 28 Jun. 2026. Conservation assessment. Field investigations indicate that Sedum anminanum is currently known from only a single population of fewer than 250 mature individuals, straddling the border between Hubei and Shaanxi provinces. The type and paratypes were collected from this same small population, occurring on a dolostone cliff wall ca. 80 m long on the northern side of the road connecting Jiepaigou and Hongyan villages. The species grows only in crevices of bare rocks. The habitat is virtually soilless, and plants here are stunted due to drought and poor nutrient availability, occurring in a fragile natural karst ecosystem. Moreover, the underdeveloped economy of the region and human activities such as road construction, quarrying, and medicinal plant collection may threaten the survival of this species. The provisional conservation status is Endangered (EN D), based on criterion D, as the population contains fewer than 250 mature individuals (IUCN Standards and Petitions Committee 2024). Notes. East Asia is one of the major centers of diversity of Sedum (Berger 1930; ’ t Hart and Bleij 2003; Thiede and Eggli 2007) and includes a significant part of the diversity of sect. Filipes, which is distributed in Bhutan, China, Japan, Myanmar, Nepal, and Sikkim (Fu and Ohba 2001). The discovery of S. anminanum increases the number of species in this section from nine to 10. In addition, S. danxiacola S. Y. Meng & B. Chen, recently discovered from sandstone mountains in the Danxia landform of southern Jiangxi Province, was placed in sect. Filipes (Meng et al. 2023). However, it has spurred leaf bases and ventrally saccate follicles (Meng et al. 2023), two characters markedly different from those of sect. Filipes, and its systematic position remains to be further determined. Molecular phylogenetic studies indicate that Sedum still contains some paraphyletic (Gontcharova and Gontcharov 2009) and polyphyletic groups (Nikulin et al. 2016). Nevertheless, the discovery of these new species not only increases species diversity but also provides new material for phylogenetic studies of Sedum. Sedum anminanum is a perennial saxicolous succulent with numerous branches and showy flowers and has the potential to become a new ornamental plant for rock gardens and roof gardens.