紫金短柱茶  Camellia zijinica M.Lin, Q.L.Ye & Q.FanCamellia zijinica

Camellia zijinica M.Lin, Q.L.Ye & Q.Fan in PhytoKeys 237: 245-255

Type-China. Guangdong: Zijin County, Guzhu Town, Mount Yuewang, in mixed forests, 23°29'N, 114°44'E, 294 m a.s.l., 22 September 2018, H.W. Wang & Q. Fan 18084 (holotype: SYS00236945! isotypes: IBSC1010670! SYS00236946! SYS00236947! SYS00236948!)

Diagnosis-Camellia zijinica is morphologically similar to C. microphylla in the flower shape and size, but differs from the latter by its young branchlets glabrous (vs. densely pubescent), the diverse leaf shape (elliptic, oblong-elliptic, obovate-elliptic or oblong-lanceolate vs. oblong-elliptic or obovate-elliptic), midvein raised slightly with sparsely pubescent or glabrous (vs. prominently with densely pubescent), fewer bracteoles and sepals (4–6 vs. 6–7), leaf adaxially matt when dried (vs. vernicose).

Description-Small evergreen shrubs, 2–5 m tall; bark yellowish brown; young branchlets reddish brown, glabrous. Leaf blades elliptic, oblong-elliptic, obovate-elliptic or oblong-lanceolate, 2–4.8 × 0.8–1.9 cm, adaxially dark green, abaxially light green, thick papery to coriaceous; petiole 1–3 mm long, pubescent; midrib prominent on both surfaces, glabrous and sometimes adaxially sparsely pubescent, secondary veins 6–7 on each side, invisible; apex rounded, acute or acuminate; margin serrulate; base cuneate. Flowers solitary, terminal or axillary, 1.5–2.3 cm in diameter, subsessile. bracteoles and sepals 4–6, caducous, outside pubescent at base, inside glabrous, margin ciliate; outer bracteoles and sepals broadly semiorbicular, partial apex bifid; inner bracteoles and sepals suborbicular to oblong-elliptic. Petals 4–6, white, distinct, glabrous, oblong-elliptic to obovate-elliptic, apically 2-lobed, 7–11×4–5 mm. Stamens 33–40, 4–5 mm long, glabrous; outer filament whorl basally connate for 1–1.5 mm. Ovary 3–4-loculed, with 2 ovules per locule, about 2 mm in diameter, tomentose. Styles 3 or 4, 1–2 mm long, connate half from the base, apically 3–4-lobed. Capsule ovoid or subglobose, ca. 1.2 cm in diameter; pericarp 1–2 mm thick, splitting into 3–4 valves. Seeds semiglobose or globose, 9–10 mm in diameter, brown, glabrous.

Phenology-Flowering from September to December, fruiting from January to September.

Etymology-The specific epithet refers to Zijin County of Guangdong Province, the type locality of the new species.

Distribution and habitat-Presently, Camellia zijinica is only known from its type locality, Zijin County of northeastern Guangdong. It is distributed in mixed forests of Danxia landscape at altitudes of 200–400 m a.s.l.

Conservation status-Only two populations of a total of about 90 mature individuals were found currently. Thus, the species could be considered as Endangered (EN; D) status according to IUCN Red List criteria (IUCN Standards and Petitions Subcommittee 2022).

Additional specimens examined-(paratypes). China. Guangdong: Zijin County, Guzhu Town, near Mount Yuewang, 23°37'N, 115°10'E, 234 m a.s.l., 12 Oct. 2022 (fl. and fr.), Z.M. Zhong 1012 (SYS); Zijin County, Guzhu Town, near Mount Yuewang, 23°29'N, 114°44'E, 310 m a.s.l., 7 June 2023 (young fr.), Z.M. Zhong 0607 (SYS), the type locality, 21 July 2023 (young fr.), Z.M. Zhong 0721 (SYS).

Zijin County of northeastern Guangdong, China

紫金短柱茶  Camellia zijinica M.Lin, Q.L.Ye & Q.Fan in PhytoKeys 237: 245-255

常绿小灌木，高2-5米；树皮黄褐色；幼枝红褐色，无毛。叶片椭圆形、长圆状椭圆形、倒卵状椭圆形或长圆状披针形，长2-4.8厘米，宽0.8-1.9厘米，上面深绿色，下面浅绿色，厚纸质至革质；叶柄长1-3毫米，被柔毛；中脉两面均明显，无毛，有时上面疏被柔毛，次脉每边6-7条，不可见；顶端圆形，急尖或渐尖；边缘有细锯齿；基部楔形。花单生，顶生或腋生，直径1.5-2.3厘米，近无柄。苞片和萼片4-6，早落，外面基部被柔毛，里面无毛，边缘有缘毛；外层苞片和萼片宽半圆形，部分顶端二裂；内层苞片和萼片近圆形至长圆状椭圆形。花瓣4-6片，白色，离生，无毛，长圆状椭圆形至倒卵状椭圆形，顶端2裂，长7-11毫米，宽4-5毫米。雄蕊33-40枚，长4-5毫米，无毛；外轮花丝基部合生，长1-1.5毫米。子房3-4室，每室有2枚胚珠，直径约2毫米，被绒毛。花柱3-4枚，长1-2毫米，自基部一半合生，顶端3-4裂。蒴果卵球形或近球形，直径约1.2厘米；果皮厚1-2毫米，裂成3-4瓣。种子半球形或球形，直径9-10毫米，棕色，无毛。