Corresponding author: Qiang Fan (
Academic editor: H. De Boer
Chen S-F, Meng K-K, Guo X-B, Zhao W-Y, Liao W-B, Fan Q (2020) A new species of
The genus
There are about 16
Morphological observations of the putative new species and its close relatives were carried out based on living plants in the field as well as dried specimens. All morphological characters were measured using a stereomicroscope with ocular micrometer (Leica S8APO, Leica Microsystems Inc., Germany). The voucher specimens were deposited in the herbarium of
Leaf samples for the putative new species were collected and stored in silica gel. The total DNA was extracted with the TIANamp Genomic DNA Kit [TIANGEN Biotech (Beijing) CO. Ltd] according to the protocol procedure, and then sent to Novogene Bioinformatics Technology (Beijing, China) Co. Ltd for quality inspection and low-coverage genome sequencing using Illumina 2000 platform following the standard Illumina sequencing procedure. Approximately 6 GB cleaned raw data was produced and assembled into circled chloroplast genomes with the perl script NOVOPlasty2.7.2 (
The alignment length of these twenty-five chloroplast genomes was 166,363bp in total, with the statistics of 1,307 parsimony-informative sites. No variable sites were detected between the two accessions of the new species but 139 variable sites were detected between the new species and
Maximum likelihood consensus tree of the new species and related species. Numbers above branches are ML bootstraps, the new species is shown in bold.
China. Yunnan Province, Malipo County, Mount Laoshan, in thin forests on the slopes of limestone hills,
This species is similar to
Evergreen small tree, 4–10 m tall, much branched; stems 8–25 cm in diameter; branchlets grey-white, terete, glabrous, 6–10 mm in diameter. Leaves spirally inserted on branches and often crowded at tips of branchlets; petioles 2–5 cm long, glabrous; stipules elliptic or ovate-lanceolate, 1–3 × 0.5–1 cm, glabrous, caducous; leaf blades oblong or broad elliptic, 20–40 × 7–12 cm, thickly coriaceous, glabrous, midrib elevated on both surfaces, secondary veins 21–30 pairs, arching slightly and often dichotomous before reaching the margin, elevated on both surfaces margin serrate, apex acute or cuspidate, base cuneate, gradually tapering to the petiole. Inflorescence in terminal panicles, 15- to 30-flowered, 8–15 cm long, 6–10 cm in diameter, with 6–10 lateral racemes, the lowermost laterals in the axils of reduced leaves (often almost entirely consisting of the stipules only), upper ones in axils of bracts, lateral racemes sometimes branched in the lower part of the inflorescence; peduncle and pedicels densely yellow-brown tomentose; bracts ovate-triangular, 1–1.5 cm long, abaxially tomentose, adaxially glabrous or sparsely pubescent; bracteoles subulate or triangular, 3–8 mm long, abaxially densely tomentose, adaxially pubescent. Flowers 2.5–3 cm in diameter. Hypanthium obconical, 4–6 × 5–7 mm, abaxially densely yellow-brown tomentose, 5-lobed, the calyx lobes ovate, 3–5 × 2–4 mm, abaxially densely tomentose, adaxially glabrous; petals white, obovate or rotund, 6–9 × 5–10 mm, shortly clawed, glabrous, margin crisped or irregularly crenulate, apex retuse; stamens 20; flaments 3–6 mm long, glabrous; anthers 1–2 mm long; ovary semi-inferior, the free apex densely villous, ovoid, 2–3 mm across, 3–5-loculed, with 2 ovules per locule; styles 3–5, densely villous, 5–7 mm long, connate at base or fused from base to middle; ovules ovoid or ellipsoid, c. 1 mm across. Pome yellow at maturity, subglobose, 2.5–3.5 cm in diameter, glabrescent, crowned by the persistent calyx lobes forming an apical beak; pericarpium fleshy, ca. 3 mm thick. Seeds (1-) 2 per fruit.
Flowering from September to October, fruiting from November to December.
The specifc epithet refers to Laoshan Mountain, the locality of the type collection.
Only two populations were found with no more than 50 mature individuals in a total area of about 5 km2. It’s about 6.5 km away between the two populations. The wood of this species is very suitable for firewood. During the expedition in 2019, we found that at least two big trees about 15 cm in diameter were felled by the local villagers. Thus the species could be considered as CR (Critically Endangered) status according to IUCN Red List criteria (B2ab(v);
The closest relative of
To distinguish these species of
Morphological comparisons amongst
Morphological comparisons amongst
Characters |
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Leaf shape and size | oblong or broad elliptic, 20–40 × 7–12 cm | oblong or oblong-obovate, 30–40 × 10–15 cm | obovate or oblanceolate, 9–23 × 3.5–13 cm |
Texture of leaves | thickly coriaceous | thickly coriaceous | thinly coriaceous |
Indumentum on the lower leaf surfaces | glabrous | densely rusty tomentose | tomentose when young, glabrescent |
Petiole length | 2–5 cm | 0.5–1 cm | 1.5–3 cm |
Lateral veins | 21–30 pairs | 20–25 pairs | 10–16 pairs |
Inflorescences | with reduced leaves, 15- to 30-flowered | without reduced leaves, 50- to 100-flowered | without reduced leaves, 30- to 60-flowered |
Flower size (diameter) | 2.5–3 cm | 1.5–2 cm | 1–2 cm |
Fruit shape and size (diameter) | subglobose, 2.5–3.5 cm | pyriform, 2–3.5 cm | ovoid or pyriform, 1.5–1.8 cm |
China. Yunnan: Malipo, Laoshan natural reserve,
1 | Leaves abaxially glabrous or glabrescent |
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– | Leaves abaxially rusty or gray persistent tomentose |
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2 | Leaves abaxially glabrous |
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– | Leaves abaxilly brownish yellow tomentose when young, glabrescent |
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3 | Leaves abaxially rusty tomentose; leaf blade 30–40 cm long; lateral veins 22–25 pairs |
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– | Leaves abaxially gray tomentose; leaf blade 7–30 cm long; lateral veins 9–16 pairs |
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4 | Leaf blade adaxially rugose; styles 5 |
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– | Leaf blade adaxially not rugose; styles 2–4, rarely 5 |
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5 | Stipule subulate; inflorescences 8–12 cm long; pome 1.5–3 cm in diam |
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– | Stipule ovate; inflorescences 6–10 cm long; pome 0.6–1 cm in diam |
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We are deeply grateful to Mrs Yun-Xiao Liu for her excellent illustration in the manuscript. This study was supported by the National Natural Science Foundation of China (31670189, 31800175), Natural Science Foundation of Guangdong Province (2016A030313326, 2017A030310421, 2018A0303130109), and the project of the Fourth Survey of Chinese Traditional Medicine Resources (2019-302-001; 2019-303-001).