Corresponding author: Qiang Fan (
Academic editor: A. Sennikov
Huang Y-S, Kang N, Zhong X-J, Liao W-B, Fan Q (2021) A new species of
Mount Xiangtoushan in Guangdong Province, China, is located in a subtropical zone with abundant rainfall, mainly a low-lying hilly landform, but has an extremely high altitude compared with the surrounding environment. A large area of granite in this region is exposed on the surface due to intense erosion and denudation and there are climax lithophytic vegetation communities with a high level of biodiversity. During fieldwork in March 2018 for the investigation of the biodiversity patterns in this mountainous region, a distinct new species,
Leaf material of the putative new species and its related species
Total DNA was extracted with the modified CTAB method (
The aligned length of ITS sequences was 638 bps in total.
Maximum Likelihood tree of the new species and related species, Numbers beside branch nodes are bootstraps. Outgroups:
China. Guangdong: Huizhou City, Xiangtoushan National Nature Reserve, Darenyan,
Herbs, perennial, basal leaves rosulate, 10–15 cm tall. Rhizome erect or obliquely erect, rather stout, 4–7 mm diam.; stolons with an apical rosette of leaves, usually producing adventitious roots. Leaves alternate; stipules leaf-like, base adnate to the petiole, densely pubescent, lanceolate, 6–8 × 1–1.5 mm, apex acuminate, margins sparsely fimbriate or fimbriate-laciniate; petioles densely pubescent, 3–5 cm long, narrowly decurrent-alate; blades narrowly ovate to ovate, apex obtuse, 1.5–3 × 1–2 cm, thinly leathery or chartaceous, densely pubescent, abaxially dark purple, 5 to 7 veins on each side of mid-rib, margin coarsely serrate, base cuneate. Flowers 15–18 mm diam.; pedicels slender, 6–10 cm long, pubescent, usually exceeding leaves, with two opposite bracteoles above middle; bracteoles lanceolate, pubescent, 4–8 mm long, margin entire, apex obtuse. Sepals green, pubescent, linear-lanceolate, 2.7–3.7 × 0.5–1 mm, margin entire, apex obtuse, base truncate or rounded. Petals whitish to light purple, with apparent violet lines, anterior one with a yellow to green patch at base; upper petals, oblong to linear-lanceolate, 2.5–3 × 0.5–0.8 mm, glabrous, margin entire, apex obtuse or erose; lateral petals with glandular hairs at the base adaxially, oblong, 4.5–5 × ca. 1.5 mm, margin entire, apex obtuse or erose; anterior petal with a short saccate spur at base, broadly spathulate or flabellate, margin entire to slightly undulate, apex obtuse. Stamens 5, unequal, puberulent, the anther thecae ca. 1 mm long, terminal appendages ca. 0.7 mm long, the posterior appendages (nectar spurs) of two anterior stamens 0.7–1 mm long. Ovary ovoid to ellipsoid, ca. 0.7 mm diam., puberulent; style ca. 1.0 mm long, conspicuous geniculate at base; stigma thickly margined on lateral sides, slightly raised at central part, shortly beaked at the apex. Capsule with brownish lines at maturity, ovoid, 6–8 mm long. Seeds brown, ovoid, 1–1.5 mm long.
Flowering from March to June, fruiting from April to July.
Populations of
Based on its slightly 2-lobed stigma and stolons topped by rosettes of leaves,
The ITS tree shows that
In conclusion, the morphological differences and the molecular phylogenetic results provide sufficient evidence for treating
Morphological differences between the species
Characters |
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Leaf shape | narrowly ovate to ovate, apex obtuse, never acute | ovate-triangular to narrowly triangular, apex acute |
Leaf margin | coarsely serrate | obtusely dentate |
Rhizome | rhizome erect or obliquely erect, rather stout, 4–7 mm diam. | rhizome obliquely ascending, slender, 1–2 mm diam. |
Aerial stem | lack of aerial stem | slender, 1–1.5 mm diam., 10–25 cm tall |
Pedicel | pedicel basal, 6–10 cm long, densely pubescent | pedicel basal or axillary, 5–8 cm long, sparsely puberulous or subglabrous |
Quantitative characteristics and significant difference analysis of the species
Quantitative characteristics |
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lp (mm) | 24.4 ± 9.9 | 53.4 ± 14.9 |
22.2 ± 5.0 | 31.4 ± 7.1 | |
22.5 ± 5.2 | 34.8 ± 7.5 | |
|
1.01 ± 0.02 | 1.11 ± 0.04 |
|
304.1 ± 73.9 | 92.3 ± 16.5 |
4.53 ± 1.47 | 1.61 ± 0.34 |
Note:
We are deeply grateful to Mrs Yun-Xiao Liu for her excellent illustration in the manuscript. This study was supported by the project of the Research on Co-evolution of Vegetation and Geological Environment of Shenzhen Dapeng Peninsula Geopark (2020F36), the project of the Fourth Survey of Chinese Traditional Medicine Resources (2019-302-001; 2019-303-001), the National Natural Science Foundation of China (31800175) and the Natural Science Foundation of Guangdong Province (2018A0303130109).
GenBank accessions for phylogenetic analysis.
Taxon | GenBank accessions |
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Figure S1
molecular data
Strict consensus tree derived from ITS sequence with Bayesian posterior probabilities in the nodes.