Research Article |
Corresponding author: Xin Chen ( chenxinzhou@hotmail.com ) Academic editor: Hanno Schaefer
© 2019 Jing Qiu, Yang Zhao, Qi Qi, Xin Chen.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Qiu J, Zhao Y, Qi Q, Chen X (2019) Sorbus lushanensis, a new species of Rosaceae from China. PhytoKeys 119: 97-105. https://doi.org/10.3897/phytokeys.119.32148
|
Sorbus lushanensis Xin Chen & Jing Qiu, sp. n. (Rosaceae), a new simple-leaved species belonging to Sorbus subg. Aria sect. Alnifoliae, is described from Anhui and Jiangxi provinces in China. Illustrations, photographs of wild plants and a distribution map are presented. The new species is morphologically similar to S. folgneri, but can be distinguished easily by its abaxially greenish-grey tomentose leaves, scale-like stipules and glabrous styles.
Sorbus, new species, taxonomy, China
Species of Sorbus are mainly distributed in the temperate areas of the Northern Hemisphere, with a centre of the highest diversity in East Asia, especially in China. The genus comprises about 100 (
The description was based on data and specimens collected in the field between 2015 and 2018 from Anhui and Jiangxi provinces. Geographical coordinates and elevations were determined using Holux m-241. Voucher specimens were deposited at the Herbarium of Nanjing Forestry University (
China. Jiangxi: Lushan City, Lushan National Park, Xianren Cave, 993 m alt., 29°34'06.24"N, 115°57'42.84"E, 05 May 2018, J. Qiu 1219 (holotype
Sorbus lushanensis is morphologically most similar to S. folgneri (C. K. Schneid.) Rehd., but differs by its leaf blade abaxially greenish-grey tomentose, stipules smaller, pedicels longer, petals larger and styles glabrous.
Tree up to 12 m tall, 14.6 cm in DBH; bole straight, bark grey to dark grey, smooth when young, with fissures, particularly at the base of trunk when mature. Branchlets greyish-brown, sparsely tomentose when young, glabrous or glabrescent at maturity, with pale brown to ochraceous lenticels. Buds turbinate or ovoid, pointed; scales reddish-brown, with white pubescent along margins. Leaves simple; stipules scale-like, 1–1.5 mm long, early deciduous; petiole (9–)13–16 (–19) mm long, greenish-grey tomentose; blades elliptic to broadly ovate, 5.9–9.2 cm long, (3–)4–5.6 cm wide, base cuneate to subcordate, apex acute to shortly acuminate, margin serrate to double serrate, densely greenish-grey tomentose abaxially, sparsely white tomentulose when young, gradually glabrous or glabrescent adaxially; venation craspedodromous, secondary veins 11–16 pairs, slightly impressed adaxially, raised abaxially. Inflorescence a compound corymb, terminal or axillary in the terminal 1–3 leaves, loosely 11–17(–26)-flowered; peduncles 3.9–6 cm long, pedicels 9.4–18.6 mm long, both sparsely white vilous. Flowers 12.5–14.2 mm in diam.; hypanthium campanulate, sparsely white vilous abaxially; sepals triangular-ovate, apex acute, 2.3–3.1 mm long, 2–2.9 mm wide, white vilous on both sides; petals white, broadly ovate or sub-rounded, apex obtuse, 5.9–7.1 mm long, 4–6.1 mm wide, glabrous, with a short claw at base. Stamens 17–20, 4.9–6.2 mm long, filaments whitish, anthers cream white to slightly yellow. Ovary 2-loculed, white tomentose apically. Styles 2, 3.1–4.6 mm long, connate to 1/3–1/2 of their length, glabrous. Infructescence glabrous, with numerous lenticels. Fruit orange-red, oblong to ovoid-oblong, 7.8–11.3 mm long, 4.2–7 mm in diam., 2-loculed, sparsely lenticellate, with an annular scar of the deciduous sepals and white tomentose inside it apically. Seeds brown, 5.46–6.48 mm long, 2.88–3.62 mm in diam., 2.04–2.72 mm thick.
Flowering from late April to early May, fruiting from September to October.
The name “lushanensis” refers to the type locality, Lushan Mountain, Jiangxi Province, China.
庐山花楸 (lu shan hua qiu).
Sorbus lushanensis is presently known only from Anhui and Jiangxi provinces (Figure
China. Anhui: Lu’an City, Tiantangzhai National Nature Reserve, 853 m alt., 31°09'00.84"N, 115°46'07.39"E, 8 May 2015, W. Du & F. Wang 0125 (
Morphological characters, such as sepals persistent or deciduous, leaves glabrous or with white or brown hair, venation craspedodromous or camptodromous, styles free or connate, are of taxonomic significance and useful in classification and delimitation of simple-leaved Sorbus taxa (
S. lushanensis | S. folgneri | |
Leaf blade | denssely greenish-grey-tomentose abaxially | densely white-tomentose abaxially |
Stipule | scale-like, 1–1.5 mm long | lanceolate, 3–4.5 mm long |
Petiole | sparsely greenish-grey-tomentose | densely white-tomentose |
Inflorescence | sparsely white vilous | densely white tomentose |
Pedicel | 9.4–18.6 mm long | 5–8 mm long |
Petal | 5.9–7.1 mm× 4–6.1 mm | 5–5.8 mm× 2.5–4.2 mm |
Style | glabrous | tomentose basally |
Sorbus lushanensis and the two sympatric species, S. alnifolia and S. folgneri are all diploid (2n=2x=34) sexual species (Chen et al. unpubl. data). Our preliminary molecular work, based on two chloroplast gene fragments, atpB-rbcL and trnL and four nuclear gene fragments, GBSSI, PGIP, PPO and WD, resolved that S. lushanensis formed as sister to S. alnifolia var. angulata S. B. Liang and they two together were resolved as sister to S. folgneri, suggesting that S. lushanensis is not most closely related to S. folgneri (Chen et al. unpubl. data). The new species can be distinguished from the other five species by its abaxially greenish-grey tomentose laminae.
1 | Leaves tomentose abaxially | 2 |
– | Leaves glabrous or sparsely hairy abaxially | 4 |
2 | Leaves orbicular-ovate or suborbicular, margins lobed | S. japonica |
– | Leaves elliptic to broadly ovate, margins serrate to double-serrate | 3 |
3 | Leaves densely white tomentose abaxially | S. folgneri |
– | Leaves densely greenish-grey tomentose abaxially | S. lushanensis |
4 | Fruits with a small annular scar apically, sepals deciduous | S. alnifolia |
– | Fruits with persistent sepals apically | 5 |
5 | Leaves elliptic to broadly ovate; fruits much larger, 10–16 × 6–13 mm | S. yuana |
– | Leaves lanceolate; fruits much smaller, 6–10 × 4–7 mm | S. zahlbruckneri |
This work was supported by Natural Science Foundation of Jiangsu Province (grant no. BK20141472) and the Priority Academic Program Development of Jiangsu Higher Education Institutions, Jiangsu Province, China (PAPD). We thank Prof. Li-Bing Zhang (MO) for the valuable comments and suggestions on the manuscript. We also thank Yuxuan Bao and Junsheng Shu for the line drawings and maps.