討論:紅星杜鵑

山羊百科，林文智老師的植物、山岳、攝影紀錄

4.Rhododendron hyperythrum Hayata　小西氏杜鵑

A small tree or shrub; branches stout; branchlets glabrous. Leaves thickly coriaceous, oblong to lanceolate, 8-10 cm long, 2.5-3 cm broad, the apex acute, apiculate at the tip, the base rounded to obtuse, the margins entire, strongly recurved, the upper surface dark, glabrous, slightly lustrous, the lower pale, dotted with minute rufous punctate glands, the costa strongly raised beneath, the secondary veins about 8-10 per side, inconspicuous; petioles 1.5-2 cm long, stout, glabrous. Flowers 3 or more, umbelled, terminal; pedicels 4-5 cm long, glandular; calyx 5-lobed, the lobes triangular, glandular; corolla white, funnelform, about 4.5 cm across, 5-lobed, the lobes rounded; stamens 10, unequal, shorter than the corolla; ovary glandular; style exserted, glandular at base. Capsules cylindric, about 2 cm long, pubescent.

Endemic. Very local in distribution, limited to the mountains north of Taipei and around Mt. Yushan.

TAIPEI: Sasaki s. n. in 1910 (Type of R. rubropunctatum Hayata), 327. CENTRAL RANGES: Konishi s. n. (Type of R. hyperythrum Hayata). CHIAYI: Mt. Yushan, Kawakami s. n. in 1907.

This species is unique in the lepidote leaves with small punctations.

4. Rhododendron hyperythrum Hayata　南湖杜鵑

Small trees or shrubs; branches stout; branchlets glabrous. Leaves thick coriaceous, oblong to lanceolate, 8-10 cm long, 2.5-3 cm broad, apex acute, apiculate, base rounded to obtuse, margin entire, strongly recurved, upper surface dark, glabrous, slightly lustrous, lower surface pale, dotted with minute rufous punctate glands, midrib strongly raised on lower surface, lateral veins 8-10 pairs, inconspicuous; petiole 1.5-2 cm long, stout, glabrous. Flowers 3 or more in terminal umbels; pedicel 4-5 cm long, glandular; calyx lobes triangular, glandular; corolla white, funnelform, ca. 4.5 cm across, 5-lobed, lobes rounded; stamens 10, unequal, shorter than corolla; ovary glandular, style exserted, glandular at base. Capsules cylindric, ca. 2 cm long, pubescent. Endemic, limited to the northern mountains of the central range.

Central Range: Konishi, s.n. (Type of R. hyperythrum Hayata).

TAICHUNG: Nanhutashan, Lu 23457. HUALIEN: Chingshuishan, Lu 14509.

长序杜鹃亚组 Subsect. Pontica Sleumer

微笑杜鹃 Rhododendron hyperythrum Hayata

常綠灌木或小喬木；小枝帶紫褐色，無毛。葉革質，橢圓狀披針形或長圓狀披針形，長7-12釐米，寬2-3.5釐米，先端急尖或短漸尖，具小尖頭，基部鈍，邊緣略反卷，上面無毛，中脈凹入，側脈10-13對，微凹，下面有棕紅色細點，中脈凸起，側脈略凸；葉柄長1.5-2.5釐米，無毛。頂生總狀傘形花序，有花約10朵；總軸長1.5-2.5釐米；花梗長3-4.5釐米，疏被腺體和叢卷毛；花萼小，長約2毫米，5齒裂，裂片扁圓形，邊緣具腺頭睫毛；花冠漏斗狀鐘形，長和寬約3-5釐米，白色，具紫色斑點，裂片5，近圓形，頂端微缺；雄蕊10，不等長，長2.5-4釐米，花絲基部被白色微柔毛，花藥長圓形，深褐色，長2-3毫米；子房圓柱狀卵球形，長約6毫米，密被腺體，花柱長2.5釐米，下半部被腺體。花期4月。

特產我國臺灣中部和北部地方。模式標本采自我國臺灣玉山。