Vaccinium usneoides Y.H.Tong, Y.J.Guo & Ting Zhang, 2023

Guo, Yong-Jie, Zhang, Ting, Ya, Ji-Dong, Zhang, Wei, Shen, Xiu-Ying, Han, Zhou-Dong, Ni, Jing-Bo, Su, Jian-Yong & Tong, Yi-Hua, 2023, Vaccinium usneoides (Ericaceae), a new species from Yunnan, China, PhytoKeys 236, pp. 187-195 : 187

publication ID	https://dx.doi.org/10.3897/phytokeys.236.112658
persistent identifier	https://treatment.plazi.org/id/8BD180ED-2D48-51B2-84F7-44036A77A207
treatment provided by	PhytoKeys by Pensoft
scientific name	Vaccinium usneoides Y.H.Tong, Y.J.Guo & Ting Zhang
status	sp. nov.

Treatment

Vaccinium usneoides Y.H.Tong, Y.J.Guo & Ting Zhang sp. nov.

Figs 1 View Figure 1 , 2 View Figure 2

Type.

China. Yunnan Province: Fugong County, Shiyueliang Xiang, Yaduo Village , Nihajiadi (also called “Shibagongli” unofficially), Gaoligong Mountain , epiphytic on trees in evergreen and deciduous broad-leaved mixed forest, 27°9′55.0″N, 98°46′44.2″E, 2497 m a.s.l., 27 May 2022 (fl.), Ting Zhang, Ji-Dong Ya & Wei Zhang 22CS21979 (holotype: KUN, barcode no. 1584163 (Fig. 3 View Figure 3 ), isotypes: IBSC, barcode no. 1003856, KUN, barcode no. 1584164) GoogleMaps .

Diagnosis.

This new species is close to V. brachyandrum in the short and hairy inflorescences (less than 3.5 cm) with many flowers and the abaxially glandular leaf blades with one basal gland per side and a caudate-acuminate apex, but can be immediately distinguished by its hanging-down (vs. scrambling) branches, much smaller leaf blades (2.5-5.5 × 0.9-1.8 cm vs. 8.5-11 × 4-6 cm) with fewer pairs of secondary veins (3-4 vs. 6-7), shorter inflorescence (1-1.5 cm vs. 1.5-3.5 cm), non-glandular tomentellate or densely pubescent (vs. glandular pubescent) inflorescence rachis and pedicel, shorter pedicel (0.7-1 mm vs. ca. 2 mm), densely white-pubescent (vs. glabrous) hypanthium and pilose (vs. glabrous) filament. A detailed morphological comparison between the two species is presented in Table 1 View Table 1 .

Description.

Evergreen shrubs, epiphytic on tree trunks, sparsely branched; roots creeping firmly on tree trunks or branches; stems 0.5-3 m long, without swollen basal tuber or root swellings. Branches hanging down, young shoots brownish or greenish, terete or slightly angled, without lenticels, densely pubescent; old ones more or less glabrescent, brownish or greyish, often obviously angled in sicco. Perennating buds dimorphic (floral perennating buds at least twice the size of vegetative perennating buds). Leaves alternate; petiole short, curved, 2-5 mm long, 1-1.5 mm wide, densely pubescent, glabrescent when mature; blade narrowly ovate to oblong, 2.5-5.5 (including caudate apex) × 0.9-1.8 cm, thickly leathery, adaxially more or less transversely wrinkled when dry, especially for young ones, abaxially with evenly distributed and caducous appressed black glandular trichomes, trichome base papillate, both sides pubescent when young, glabrous when mature, base rounded to broadly cuneate, with 1 basal gland per side at ca. 1 mm distance from the junction of leaf blade base and petiole, margin entire, revolute, with a ca. 0.5 mm broad, cartilaginous edge, apex caudate-acuminate; veins impressed adaxially, more so when dry, obscure abaxially, secondary veins 3-4 per side, tertiary veins slightly prominent. Inflorescence short racemose, 1-1.5 cm long, axillary on biennial branches, shorter than and shaded by leaf blades, 8-14-flowered. Peduncle very short, inflorescence rachis 0.7-1 cm long, white-tomentellate or densely white-pubescent; bracts red on exposed part, greenish on covered part, broadly obovate, cucullate, 5-6 × 6-7 mm, abaxially more or less white-pubescent on mid-vein, more so on lower half, adaxially glabrous, margin ciliate, caducous; bracteoles 2, inserted at base of pedicel, greenish, sometimes tinged with red, obovate, 3.5-4 × 2-2.5 mm, indumentum similar to bracts, caducous. Pedicels greenish, very short, 0.5-1 mm long, densely white-pubescent, articulate with the hypanthium. Hypanthium greenish, obconical, 1-1.5 × 1-1.5 mm, densely white-pubescent, more so at base; calyx limb lobed nearly to base, lobes 5, green, more or less tinged with red, triangular, ca. 2 × 1.5 mm, abaxially white-pubescent at apex, otherwise glabrous, adaxially glabrous, apex acuminate, margin ciliate. Corolla red, urceolate-campanulate, slightly angled when young, 3.5-4 × ca. 3 mm, tube glabrous on both sides; lobes 5, ovate-triangular, reflexed, ca. 0.8 × 1 mm, abaxially white-pubescent at apex, otherwise glabrous, adaxially papillose, apex acuminate. Stamens 10, 2.8-3 mm long; filaments flat, slightly S-shaped, 1-1.2 mm long, papillose on both sides, margin pilose; anthers 1.8-2 mm long, thecae slightly longer than or nearly as equal as tubules; spurs 2, borne at abaxial base of tubules, 0.7-0.8 mm long, spreading. Disc yellowish-green, annular, glabrous; style cylindrical, slightly angled in sicco, 2.7-3 mm long, glabrous, stigma truncate; ovary pseudo-10-locular, each locule with several ovules. Fruiting pedicels 1-3.5 mm long; berries pale green to green when young, yellowish-green to purplish-red or dark purple when mature, globose, 4.5-6 mm in diam., densely white-pubescent, with persistent calyx lobes appressed at apex, ripe berries a little bitter. Seeds ovoid, 0.7-0.8 × 0.5-0.7 mm, testa brownish, reticulate.

Etymology.

The species epithet is derived from the genus of beard lichen " Usnea " and the suffix "- oides ", which means the habit of this new species looks very much like beard lichen on trees from a distance. Chinese name is given as松萝越橘 (Pinyin: sōng luó yuè jú).

Distribution and habitat.

This species is currently known only from the type locality, i.e. the part of the Gaoligong Mountain in Fugong County. It grows on trees in mountainous evergreen and deciduous broad-leaved mixed forests at elevations of 2400-2800 m a.s.l.

Conservation status.

Vaccinium usneoides is not rare in the type locality and the whole distribution area is under the protection of Gaoligongshan National Nature Reserve. Thus, the threat risk seems to be low. Since the type locality is very near the border of China and Myanmar, this species is probably also distributed in the adjacent area of Myanmar. Thus, it is best to assign a status of 'Data Deficient’ (DD) for this species following the IUCN Red List Categories and Criteria ( IUCN Standards and Petitions Committee 2022).

Phenology.

Flowering in May-June and fruiting in October-November.

Additional specimens examined.

Vaccinium usneoides (paratypes): the same locality with holotype: 27°9′57.78″N, 98°46′14.91″E, 2661 m a.s.l., 27 October 2022 (fr.), Yong-Jie Guo, Zhou-Dong Han & Xiu-Ying Shen 22CS22598 (IBSC, barcode no. 1003853, KUN, barcode nos. 1584165 & 1584166); 27°9′56.89″N, 98°46′14.63″E, 2652 m a.s.l., 27 October 2022 (fr.), Yong-Jie Guo, Zhou-Dong Han & Xiu-Ying Shen 22CS24002 (IBSC, barcode no. 1003856, KUN, barcode nos. 1584167 & 1584168); 27°9′46.08″N, 98°46′39.98″E, 2544 m a.s.l., 27 October 2022 (fr.), Yong-Jie Guo, Zhou-Dong Han & Xiu-Ying Shen 22CS24003 (IBSC, barcode no. 1003855, KUN, barcode no. 1584169); 27°9′39.6″N, 98°46′56.06″E, 2444 m a.s.l., 10 March 2023, Yi-Hua Tong, Jing-Bo Ni, Bing-Mou Wang & Wei-Hao Pan TYH-2637 (IBSC).

Examined specimens of Vaccinium brachyandrum .

China. Yunnan Province: Tengchong, Houqiao, 2720 m a.s.l., 18 May 1964, Su Kung Wu 6629 (holotype KUN1209465, isotype KUN1209466); ibid., 25°24′16.700″N, 98°8′43.869″E, 2564 m a.s.l., 22 August 2022, Yong-Jie Guo & Zhong-Lan Yang 22CS22523 (IBSC, KUN); Lushui, Pianma, Fengxueyakou, 25°59′12.779″N, 98°40′3.828″E, 2691 m a.s.l., 23 May 2022, Ting Zhang, Ji-Dong Ya & Wei Zhang 22CS21913 (IBSC, KUN); ibid., 25°59′12.72″N, 98°40′3.9″E, 2705 m a.s.l., 28 October 2022, Yong-Jie Guo & Zhou-Dong Han 22CS22599 (IBSC, KUN); ibid., 25°59′0.76″N, 98°40′5.03″E, 2782 m a.s.l., 11 March 2023, Yi-Hua Tong, Jing-Bo Ni, Bing-Mou Wang & Wei-Hao Pan TYH-2643 (IBSC) & TYH-2644 (IBSC).