目前为止，中国西南野生生物种质资源库共保藏该物种: 种子5份; DNA材料15份;

• 科:杜鹃花科    Ericaceae
• 属:杜鹃属    Rhododendron
• 种:凸尖杜鹃   Rhododendron sinogrande

237. Rhododendron sinogrande I. B. Balfour & W. W. Smith, Notes Roy. Bot. Gard. Edinburgh. 9: 274. 1916. 凸尖杜鹃 tu jian du juan Rhododendron sinograndeCredit: Harvard University Herbaria Rhododendron sinogrande var. boreale Tagg & Forrest.Trees, 5–12 m tall; shoots stout, 1–1.5 cm in diam., thinly silvery-gray-tomentose. Petiole stout, 30–50 mm, with silvery appressed indumentum; leaf blade thickly leathery, oblong-elliptic to oblong-oblanceolate, 20–70 × 8–30 cm; base broadly cuneate or rounded; margin slightly revolute; apex rounded or obtuse and stiffly mucronate; abaxial surface silvery-gray to buff, indumentum compacted and agglutinated; adaxial surface glabrous; midrib prominent abaxially. Inflorescence racemose-umbellate, 15–20-flowered; rachis 30–60 mm. Pedicel stout, 3–5 cm, with a dense buff tomentum; calyx oblique; lobes 8(–10), ca. 2 mm, triangular, tomentose or glabrescent; corolla ventricose-campanulate, fleshy, creamy-white to pale yellow, 4.5–5.5 cm, with crimson nectar pouches at base inside; lobes 8(–10); stamens 18–20, unequal, filaments densely puberulent at base; ovary ca. 10 mm, densely pale brown-tomentose, eglandular; style glabrous, stigma large and discoid. Peduncle 6–6.5 cm. Capsule large and woody, cylindric, slightly curved, 40–70 × 14–17 mm, densely rusty-tomentose. Fl. Apr–May, fr. Aug–Oct.Coniferous forests in alpine regions, Rhododendron thickets; 2100–3600 m. SE Xizang, W Yunnan [NE Myanmar].【引自：Flora of China】

常绿乔木，高5-12米；幼枝粗壮，直径1-1.5厘米，被薄层银灰色毛被。叶大，厚革质，长圆状椭圆形或长圆状倒披针形，长20-70厘米，宽8-30厘米，先端圆或钝，具硬凸尖头，基部宽楔形或圆形，边缘略反卷，上面无毛，微有皱纹，中脉凹入或平坦，侧脉15-18对，凹入，下面具光泽，被银灰色至淡黄色粘结状紧贴的毛被，中脉极度凸起，侧脉显著；叶柄粗，长3-5厘米，被银灰色紧贴的毛被。顶生总状伞形花序或伞形花序，有花15-20朵，总轴长3-6厘米，被微绒毛，无腺体；花梗粗壮，长3-5厘米，密被淡黄色微绒毛；花萼小，偏斜，长约2毫米，8-10裂，裂片三角形，被微柔毛或近无毛；花冠宽钟形，偏斜，肉质，长4.5-5.5厘米，乳白色至淡黄色，里面基部具深红色蜜腺囊，8-10裂，裂片圆形，长约1.5厘米，宽2厘米，顶端微有缺刻；雄蕊8-20，不等长，长1.5-2.5厘米，花丝基部密被微柔毛，花药椭圆形，黄褐色，长3毫米；雌蕊稍短于花冠，长于雄蕊；子房圆锥形，长约1厘米，密被淡棕色绒毛，无腺体，花柱无毛，柱头大，盘状。蒴果大，木质，圆柱形，长4-7厘米，直径1.4-2.7厘米，密被锈色绒毛，略弯，果梗长6-6.5厘米。花期4-5月，果期8-10月。 【引自：中国植物志】