双柏山茶 Camellia shuangbaiensis G.P.Yang & B.H.WuCamellia shuangbaiensis

Camellia shuangbaiensis G.P.Yang & B.H.Wu in PhytoKeys 254: 143–149 (2025)

Type. China Yunnan: Shuangbai County, Damaidi Township, in ravine. 24°22.44'N, 101°50.84'E, 1740 m a.s.l., 6 June 2024 (fl.), S. Qu and G.P. Yang Lg2024132 (holotype: CNGB!; isotypes: IBSC!).

Diagnosis. Camellia shuangbaiensis morphologically resembles C. mileensis T.L.Ming and C. hongkongensis Seem., but it can be distinguished from the latter two species by its leaves with ovate shape, tomentose abaxial surface and rounded leaf base and bracteoles/sepals 14–16.

Description. Small evergreen tree, 2–4 m tall; bark greyish brown, rough; current-year branchlets densely covered with whitish pubescence. Leaf blades ovate to elliptic, leaf apex acuminate to acute, leaf base round, 3.5–6.5 × 2.3–4 cm, leaf blade leathery, adaxially dark green, pubescent along the midrib, abaxially light green, tomentose, more or less punctate; midrib prominent on both surfaces, secondary veins 5–6 pairs, elevated on adaxial surface and impressed on abaxial surface; petiole 2–5 mm long, pubescent. Flowers solitary or sometimes 2 or 3-clustered, terminal, subterminal or axillary, 2–4 cm in diameter, sessile. Bracteoles and sepals 14–16, semipersistent, outside brownish silky pubescent, inside glabrous; outer bracteoles and sepals broadly semiorbicular, rarely apex bifid; inner bracteoles and sepals suborbicular to oblong-elliptic. Petals 6–7, red, basally slightly connate, oblong-elliptic to obovate-elliptic, apex round, 7–11 × 4–5 mm, outside white silky pubescent along ridge. Stamens 33–40, 1.5–2.8 cm long, glabrous; outer filament whorl basally connate for 1–1.5 cm. Ovary 3-loculed, about 2.5–3.3 mm in diameter, tomentose. Styles 3, distinct, glabrous, 1.4–1.75 cm long. Capsule ovoid or subglobose, surface furfuraceous, 1.7–1.9 cm in diameter; pericarp ca. 2 mm thick.

Phenology. Flowering in February, fruiting in June.

Etymology. The specific epithet “shuangbaiensis” refers to Shuangbai County of Yunnan Province, the type locality of the new species

Distribution and habitat. Presently, Camellia shuangbaiensis is only known from its type locality, Shuangbai County of central Yunnan. It is distributed in mountain slope mixed forest habitat at altitudes of 1500–2000 m a.s.l.

Additional specimens examined. China • Yunnan: Shuangbai County, Damaidi Town, Damaidi Country, 24°22.44'N, 101°50.84'E, 1740 m a.s.l., 5 February. 2024 (fl.), S. Qu and G.P. Yang Lg2024133 (CNGB; SYS); • ibid., 11 June 2024 (young fr.), S. Qu and F.F. Li Lg2024135 (SYS); • ibid., 11 June 2024 (young fr.), S. Qu and F.F. Li Lg2024136 (SYS); • ibid., 11 June 2024 (young fr.), S. Qu and F.F. Li Lg2024137 (SYS); • ibid., 11 June 2024 (young fr.), S. Qu and F.F. Li Lg2024138 (SYS); • ibid., 11 June 2024 (young fr.), S. Qu and F.F. Li Lg2024139 (SYS); • ibid., 11 June 2024 (young fr.), S. Qu and F.F. Li Lg2024140 (SYS).

双柏山茶 Camellia shuangbaiensis G.P.Yang & B.H.Wu in PhytoKeys 254: 143–149 (2025)

特征集要：双柏山茶（Camellia shuangbaiensis）在形态上与弥勒山茶（C. mileensis T.L.Ming）和香港山茶（C. hongkongensis Seem.）相似，但可通过叶片卵形、背面被绒毛、叶基部圆形和小苞片/萼片14-16与后两种区分。

常绿小乔木，高 2-4 米；树皮灰褐色，粗糙；当年生小枝密被白色短柔毛。叶片卵形到椭圆形，叶先端渐尖到锐尖，叶基圆形， 3.5-6.5 x 2.3-4 厘米，叶片革质，正面深绿色，沿中脉被短柔毛，背面淡绿色，被绒毛，或多或少有点；中脉两面突出，次脉5-6对，正面隆起，背面凹陷；叶柄长2-5毫米，被短柔毛。花单生或有时 2 或 3 簇生，顶生、近顶生或腋生，直径 2-4 厘米，无梗。小苞片和萼片14-16，半宿存，外面被带褐色绢状短柔毛，里面无毛；外部小苞片和萼片宽半圆形，很少先端2裂；内部小苞片和萼片近圆形到长圆状椭圆形。花瓣 6-7，红色，基部稍合生，长圆状椭圆形到倒卵状椭圆形，先端圆形， 7-11 x 4-5 毫米，外面沿脊被白色绢状短柔毛。雄蕊 33-40 枚，长 1.5-2.8 厘米，无毛；外轮花丝基部合生达 1-1.5 厘米。子房 3 室，直径约 2.5-3.3 毫米，被绒毛。花柱 3，离生，无毛，长 1.4-1.75 厘米。蒴果卵球形或近球形，表面软鳞片状，直径 1.7-1.9 厘米；果皮厚约 2 毫米。花期:二月开花，六月结果。