Doronicum micranthum (Asteraceae, Senecioneae): a distinct new species from western Qinling, China

37 Doronicum micranthum (Asteraceae, Senecioneae): a distinct new species from western Qinling, China Zengfu Bai1,2, Guiyuan Zhang3, Zhihua Zhang1, Anzhong Li3, Hao Li3, Geyang Wang3, Xuelin Chen1,2, Ji Zhang1,2 1 College of Life Sciences, Northwest Normal University, Lanzhou, 730070, Gansu, China 2 Institute of New Rural Development, Northwest Normal University, Lanzhou, 730070, Gansu, China 3 Gansu Xiaolongshan National Nature Reserve Management and Protection Center, Tianshui, 741020, Gansu, China Corresponding authors: Xuelin Chen ([email protected]); Ji Zhang ([email protected]) Copyright: © Zengfu Bai et al. This is an open access article distributed under terms of the Creative Commons Attribution License (Attribution 4.0 International – CC BY 4.0). Research Article Abstract Doronicum micranthum (Asteraceae, Senecioneae), a new species from Hui County and Liangdang County in southeastern Gansu Province, China, is described and illustrated. This species is closely related to D. stenoglossum Maxim. and D. conaense Y.L.Chen, with which it shares the following characters: the ray florets are equal to or shorter than the involucre, and the small capitula are arranged in racemes at the stem apex. It differs by having swollen (vs. not swollen) rhizomes, smaller capitula (0.5–1.4 vs. 2–2.5 cm in diameter), and all florets’ achenes that are glabrous and lack a pappus (vs. achenes in all florets puberulent, pappus present, or glabrous and without pappus in ray florets, densely pubescent and bearing a pappus in disk florets). Key words: Asteraceae, morphology, taxonomy, western Qinling Introduction Doronicum L. is primarily distributed in the temperate mountainous regions of Europe and Asia, as well as in northern Africa. Species of this genus grow in open or forested habitats from sea level up to 5000 m. Álvarez Fernández (2003) recognized 26 species within Doronicum, while approximately 40 species have been reported worldwide in the Flora of China, with seven occurring in China (including four endemics) (Chen and Nordenstam 2011). All species are perennial herbs with alternate leaves; the basal leaves possess long petioles, whereas those of the cauline ones are sessile and semi-amplexicaul at the base; the capitula are radiate; and the achenes are cylindrical or obcylindrical with 10 longitudinal ribs. This genus is typically characterized by relatively large and brightly colored capitula. Some species are commonly cultivated as ornamentals, while others are valued for their medicinal properties (Chen 1999). The genus is traditionally placed within the tribe Senecioneae (Cassini 1819; Bentham 1873; Hoffmann 1892; Nordenstam 1977; Bremer 1994; Fei et al. 2019), a placement also supported by chloroplast ndhF gene sequence data (Álvarez Fernández and Nieto Feliner 1999). However, the generic Academic editor: Bing Liu Received: 17 July 2025 Accepted: 6 November 2025 Published: 2 December 2025 Citation: Bai Z, Zhang G, Zhang Z, Li A, Li H, Wang G, Chen X, Zhang J (2025) Doronicum micranthum (Asteraceae, Senecioneae): a distinct new species from western Qinling, China. PhytoKeys 267: 37–42. https://doi. org/10.3897/phytokeys.267.165470 PhytoKeys 267: 37–42 (2025) DOI: 10.3897/phytokeys.267.165470 38 PhytoKeys 267: 37–42 (2025), DOI: 10.3897/phytokeys.267.165470 Zengfu Bai et al.: Doronicum micranthum boundaries have undergone continuous changes, most notably through the exclusion of species now placed in Arnica, Aster, and Nannoglottis (Álvarez Fernández and Nieto Feliner 2000). Located in the western Qinling Mountains’ biodiverse upper Jialing River basin, the Gansu Xiaolongshan National Nature Reserve spans Hui and Liangdang Counties in Longnan City, situated within a key ecological transition zone supported by complex geology and varied climates. During the 2025 field investigation in Gansu Province, we discovered several populations of an unusual Doronicum species in Yuguan Town (Hui County) and Yunping Town (Liangdang County) (Fig. 3). The plants are morphologically distinct, characterized by very small capitula and completely glabrous achenes. Morphological comparisons with related taxa, literature review, and examination of herbarium specimens indicate its closest affinity with D. conaense and D. stenoglossum. However, it differs from these species in several aspects (Figs 1, 2). We therefore conclude that this plant represents a previously undescribed species, which we describe here as Doronicum micranthum Z.F.Bai & Xue L.Chen. Materials and methods Measurements and descriptions of the new species are based on field-collected living material and the subsequent dried herbarium specimens. Voucher specimens were deposited in the Herbarium of the College of Life Sciences, Northwest Normal University (NWTC). Measurements were taken using a ruler, and micromorphological structures were observed and measured using a stereomicroscope. To assess the morphological differences among related species, we consulted relevant taxonomic literature and examined herbarium specimens from HNWP, KUN, NWTC, PE, and TIE (Chen 1998, 1999; Chen and Nordenstam 2011). Taxonomic treatment Doronicum micranthum Z.F.Bai & Xue L.Chen, sp. nov. urn:lsid:ipni.org:names:77372725-1 Figs 1, 2 Type materials. China • Gansu: Hui County, Yuguan town, in broad-leaved forests, alt. 2000 m, 10 May 2025, Zengfu Bai BZF20250510005 (holotype NWTC!; isotypes NWTC!). Paratypes. China • Gansu: Hui County, 10 May 2025, Z.F.Bai & Xue L.Chen 20250510006, 20250510007 (NWTC); 21 June 2025, Zhi Zheng 637 (NWTC). Description. Perennial herb. Rhizome fleshy, swollen, with numerous fibrous roots. Stems solitary, erect, 35–60 cm tall, unbranched or bearing only floral branches, green, sparsely glandular-puberulent. Basal leaves long-petiolate; leaf blades obovate-oblong, 1.2–7 cm long, 1–6.5 cm wide, apex rounded, base subcordate; petioles slender, 3.5–7.5 cm long, narrowly winged. Mid-cauline leaves ovate-oblong, sessile, 5.5–10.5 cm long, 3.5–7 cm wide, apex obtuse or mucronate, base cordate, semiamplexicaul, margin remotely dentate proximally, subentire distally, both surfaces subglabrous; upper cauline leaves ovate or 39 PhytoKeys 267: 37–42 (2025), DOI: 10.3897/phytokeys.267.165470 Zengfu Bai et al.: Doronicum micranthum Figure 1. Habitat and habit of Doronicum micranthum. ovate-lanceolate, 2–8 cm long, 1.5–6 cm wide, apex shortly acuminate, base cordate, semiamplexicaul. Capitula (including ray florets) 0.5–1.4 cm in diam., usually solitary; peduncles 2–13.5 cm long, glandular-pubescent. Involucres hemispheric, 4–8 mm long, 0.5–1.2 cm in diam.; phyllaries in 2–3 series, outer ones lanceolate, 1.5–2 mm wide, margin ciliate, abaxially glandular-pubescent on lower half, distally glabrous or subglabrous; inner ones narrowly lanceolate, ca. 1 mm wide, margin ciliate, abaxially glandular-pubescent; apex of all phyllaries long-acuminate, equal with or slightly longer than disk florets. Ray florets 18–25, yellow, 5–8 mm long; tube 1–2 mm long, glabrous; lamina oblong or oblong-elliptic, slightly spreading, 4–6 mm long, ca. 2 mm wide, 4-veined, apex 2–3-denticulate. Disk florets numerous; corolla yellowish green, 3–4 mm long; tube ca. 1 mm long; limb campanulate-funnelform, lobes ovate-triangular; anthers usually not exserted, ca. 1.5 mm long, base obtuse; style branches bifid, apex obtuse or truncate. Achenes brown, 10-ribbed. Pappus absent in all florets. Phenology. Flowering from May to June; fruiting from July to August. Etymology. The specific epithet refers to the smallest capitula among all known species in Doronicum in China. Hence, the Chinese name“小花多榔菊 (xiǎo huā duō láng jú)” is suggested. 40 PhytoKeys 267: 37–42 (2025), DOI: 10.3897/phytokeys.267.165470 Zengfu Bai et al.: Doronicum micranthum Figure 3. Distribution of Doronicum micranthum. Figure 2. Detailed morphology of Doronicum micranthum. A. Habit; B. Rhizome; C. Leaves; D. Top view of capitula; E. Bottom view of capitula; F. Ray florets; G. Disk florets; H. Phyllaries; I. Infructescence. 41 PhytoKeys 267: 37–42 (2025), DOI: 10.3897/phytokeys.267.165470 Zengfu Bai et al.: Doronicum micranthum Distribution and habitat. Doronicum micranthum is hitherto known from Hui County (33°39'39.23"N, 106°19'45.32"E; 33°40'45.20"N, 106°21'56.13"E), Liangdang County (33°41'27"N, 106°19'35"E) of southeastern Gansu (Fig. 3). It grows in broad-leaved forests at elevations of 2000–2260 m. Notes. Doronicum micranthum is unambiguously distinguished from D. conaense, D. stenoglossum, and D. calotum by its characteristically small capitula (consistently less than 1.5 cm in diameter) and the complete absence of a pappus in all florets. Furthermore, D. micranthum possesses a prominently enlarged rhizome, a diagnostic feature not shared by the other three species discussed here. In contrast, D. conaense, D. stenoglossum, and D. calotum all possess larger capitula (exceeding 1.5 cm in diameter) and a pappus, though its distribution varies: a pappus is present in all florets of both D. stenoglossum and D. calotum, whereas in D. conaense, the ray florets are epappose and the disk florets are pappose. Key to species of Doronicum in China 1 Capitula less than 1.5 cm in diameter; pappus absent .........D. micranthum – Capitula more than 1.5 cm in diameter; pappus present or absent ........... 2 2 Ray florets as long as or shorter than involucre; capitula 1.5–2(–2.5) cm in diam., arranged in racemes ......................................................................3 – Ray florets distinctly longer than involucre; capitula 5–7 cm in diam., solitary, rarely 2 .................................................................................................... 4 3 Peduncle thick, 3–8 cm, apex dilated; ray lamina oblong; achenes heteromorphic (ray florets glabrous, disk florets puberulent).............D. conaense – Peduncle slender, 1–1.5 cm; ray lamina linear; achenes homomorphic (all puberulent) ...........................................................................D. stenoglossum 4 Ray florets glabrous and epappose, disk florets pappose and hairy .........5 – All florets with pappus ..................................................................................6 5 Basal leaves elliptic; petiole 16–20 cm; ray floret tube glabrous ................. ...............................................................................................D. oblongifolium – Basal leaves obovate; petiole 4–15 cm, winged; ray floret tube glandular hairy ...................................................................................... D. turkestanicum 6 Rhizomes slender, basal leaves obovate-spatulate or oblong-elliptic, involucre 3–3.5 cm in diam.; ray florets 2.2–2.8 cm .........................D. calotum – Rhizomes robust; basal leaves ovate or ovate-oblong, rarely orbicular, involucre 2–3 cm in diam.; ray florets 1.6–2.5 cm........................ D. altaicum Additional information Conflict of interest The authors have declared that no competing interests exist. Ethical statement No ethical statement was reported. Use of AI No use of AI was reported. 42 PhytoKeys 267: 37–42 (2025), DOI: 10.3897/phytokeys.267.165470 Zengfu Bai et al.: Doronicum micranthum Funding Common Key Technologies for the Enhancement of the Lanzhou Lily Industry: Research, Development, and Integrated Application (GXH20220617-5); Abies chensiensis population survey of Gansu Xiaolongshan National Nature Reserve, 2025 Central Government Financial Subsidy Project for National Nature Reserves. Author contributions BZF and ZGY contributed equally to this publication: performed data analysis and drafted the manuscript; ZZH: conceived the study and designed the experiments; LH and LAZ: collected the species samples and performed the experiments; WGY: collected the species samples; CXL: conceived the study, acquired funding, collected and identified the species samples, and curated the data; ZJ: conceived the study, acquired funding, and critically reviewed the manuscript. All authors have read and agreed to the contents of the manuscript. Data availability All of the data that support the findings of this study are available in the main text. References Álvarez Fernández I (2003) Systematics of Eurasian and North African Doronicum (Asteraceae: Senecioneae). Annals of the Missouri Botanical Garden 90: 319–389. https://doi.org/10.2307/3298534 Álvarez Fernández I, Nieto Feliner G (1999) Lectotypification of 16 species names in Doronicum (Asteraceae, Senecioneae). Taxon 48: 801–806. https://doi. org/10.2307/1223652 Álvarez Fernández I, Nieto Feliner G (2000) A new species of Doronicum (Asteraceae, Senecioneae) from central China. Annales Botanici Fennici 37: 249–253. Bentham G (1873) Notes on the classification, history, and geographical distribution of Compositae. Linnean Society Transactions 13(70–72): 335–577. https://doi. org/10.1111/j.1095-8339.1873.tb02575.x Bremer K (1994) Asteraceae. Cladistics & Classification. Timber Press, Portland, Oregon, 752 pp. Cassini H (1819) Suite du sixième mémoire sur la famille des synanthérées. Journal de Physique, de Chimie, d’Histoire Naturelle et des Arts 88: 189–204. Chen YL (1998) Two new species of Doronicum Linn. (Compositae) from China. Acta Phytotaxonomica Sinica 36(1): 73–76. Chen YL (1999) Doronicum Linnaeus. In: Chen YL (Ed.) Flora Reipublicae Popularis Sinicae, Vol. 77(1). Science Press, Beijing, 12 pp. Chen YL, Nordenstam B (2011) Doronicum Linnaeus. In: Wu ZY, Raven PH (Eds) Flora of China, Vols 20–21. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis, 372–375. Fei WQ, Wu X, Ren C, Chen YS (2019) The identity of Doronicum calotum (Asteraceae, Senecioneae). Phytotaxa 423(3): 211–214. https://doi.org/10.11646/phytotaxa.423.3.10 Hoffmann O (1890–1894) Compositae. In: Engler A, Prantl K (Eds) Die Natürlichen Pflanzenfamilien, Vol. 4. Englemann, Leipzig, 87–387. Nordenstam B (1977) Senecioneae and Liabeae: systematic review. In: Heywood JB, Turner BL (Eds) The Biology and Chemistry of the Compositae. Academic Press, London, 799–830.