Sageretia liuzhouensis Y. Yang & H. Sun 2017, sp. nov.
Creators: name: Yang, Yi
name: Zhang, Jian-Wen
name: Sun, Lu
name: Sun, Hang
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Rosales
Rhamnaceae
Sageretia
Sageretia liuzhouensis

description: Sageretia liuzhouensis Y. Yang & H. Sun, sp. nov.   
 Type:— CHINA. Guangxi, Liuzhou, Yufeng District, Da Longtan, Yanshi-shan (N24.280093°, E109.422459°), 10 November 2016, Y. Yang, yangyi _ 33 (holotype: KUN1301357!; isotype: KUN1301355!, KUN1301356!).   
Evergreen shrubs erect, 1–2.5 m tall, unarmed. Old branches charcoal-gray, glabrous; new branches greenish, with white or yellowish pubescence. Leaves alternate; petioles (1) 2–5 (8) mm long, glabrous, sometimes adaxially puberulent; leaf blades adaxially shiny, green, greyish-green when dry, usually oblong, elliptic or ovate-elliptic, rarely ellipticlanceolate, (2) 2.5–5.5 (7) × (0.8) 1–2.5 (3) cm, leathery or thin leathery, abaxially yellow-green, both surface glabrous, while sparely villous when young, lateral veins (5) 6–9 (10) pairs, midvein and lateral veins prominent abaxially, impressed adaxially, base cordate, subcordate, rounded, subrounded or cuneate, margin often revolute, serrulate, apex obtuse, acute or acuminate. Flowers yellowish-white, sessile, glabrous, usually 1–6 fascicled in terminal or axillary lax spikes or paniculate spikes; rachises 3–10 cm, sparsely pubescent. Sepals triangular to triangular-ovate, ca. 1 mm, adaxially keeled and hooded. Petals spatulate, shorter than sepals. Stamens slightly longer than petals; anthers acute. Styles short, thick; stigmas short, 3-fid, sometimes entire. Drupes purple-black at maturity, obovoid-globose, ca. 5 mm in diam. Flowering Oct–Nov, fruiting Jan–Feb. Fig. 2 and 3.  
 Distribution and habitat:—Currently known only from six hills very close to each other in the suburbs of Liuzhou City, north central Guangxi, south China, at the elevation of 100–300 m, occurring in sparse forests or thickets on the top of towering limestone hills.   
 Additional specimens examined:— CHINA. Guangxi, Liuzhou City, Da Longtan, Lei-shan, 1 January 2016, Y. Yang & L. Sun, yygx 12 (KUN). Liuzhou City, E-shan, 14 September 2016, Y. Yang, yygx 30 (KUN). Liuzhou City, Da Longtan, 10 November 2016, Y. Yang, yangyi 19 (KUN). Liuzhou City, Ma’an-shan, 10 November 2016, Y, Yang, yangyi 32 (KUN). Liuzhou City, Da Longtan, 26 April 1989, Longtan-Doule Team 64 (IBK). Liuzhou City, Da Longtan, Paotai-shan, 5 May 1989, Longtan-Doule Team 357 (IBK).   
 The new species is morphologically most similar to Sageretia camelliifolia with unarmed branches and leathery, glabrous leaves. They are restricted to sparse forests or thickets on top of limestone hills (Fig. 2A) and share sunny, dry habitats (Fig. 2B). Nevertheless, the new species differs from S. camelliifolia by having a pubescent inflorescence rachis (Fig. 2E, Fig. 3B), charcoal-gray branches (Fig. 2F), smaller leaves and shorter petioles (Table 2). The other morphologically similar species is S. thea. Although it is similar to the new species with a pubescent inflorescence rachis and in leaf size, the new species differs from S. thea in the number of lateral veins (5) 6–9 (10) in the new species (Fig. 2F, Fig. 3A) vs. 3–5 (7) in S. thea and leaf texture (leathery or thin leathery vs. papery; Table 2).   
 The recognition of the new species is also supported by our molecular phylogenetic analyses (Fig. 1). The phylogeny suggests that S. camelliifolia or S. thea are not the sister of the new species. S. camelliifolia is within a clade separated from the new species clade and S. thea is more closely related to S. subcaudata and S. rugosa than the new species.
description: Published as part of Yang, Yi, Zhang, Jian-Wen, Sun, Lu & Sun, Hang, 2017, Sageretia liuzhouensis (Rhamnaceae), a new species from Guangxi, China, pp. 229-237 in Phytotaxa 309 (3) on pages 232-234, DOI: 10.11646/phytotaxa.309.3.3, http://zenodo.org/record/13702150