討論:雙花金絲桃
山羊百科，林文智老師的植物、山岳、攝影紀錄
4. Hypericum geminiflorum Hemsl.
4a. var. geminiflorum. 雙花金絲桃 Pl.331, Photo 312
Lax shrub 0.5-1.5 m tall, often spreading or pendulous; branches 4-lined and ± flattened when young, eventually terete. Leaves subsessile; lamina 2-4.5 cm long, 0.6-2.2 cm broad, oblong to elliptic or ovate-oblong, apex acute to rounded, usually apiculate, base cuneate, chartaceous, paler beneath, with ± strong submarginal vein, reticulate venation not or scarcely visible and only pale glandular dots, sometimes prominent above. Inflorescence 1-3-flowered, terminal, sometimes with up to 14 pairs of axillary flowers on short 1(2-3)-flowered branches; flowers 2-3 cm in diam., ± plane, in bud ovoid, acute or subacute; sepals 1-3.5 mm long, 1-2 mm broad, broadly ovate or triangular to oblong-lanceolate or subcircular, subacute to rounded, with entire margin, spreading to ascending in fruit; petals 9-15 mm long, 5-7 mm broad, narrowly obovate, bright yellow (? Rarely white), deciduous; stamen fascicles 5, deciduous, each with 6-11 stamens; anthers bright yellow, with amber gland; ovary 2.5-3.5 mm long, narrowly ellipsoid, 5-locular, styles 1.3-2 times as long, completely united. Capsule 8-11 mm long, 3-5 mm broad, narrowly cylindric; seed ca. 1.5 mm long, dark reddish-brown, scarcely carinate, with terminal appendage sometimes expanded.
The Philippines (Luzon) and Southern Taiwan. On open stony ground, below 300-800 m (1,000-1,500 m on Luzon).
KAOHSIUNG: Ape's Hill, Henry 1155. PINGTUNG: Kaoshihfo, Hayata & Sasaki s. n. 1912; S. Cape, Henry 1324. TAITUNG: Hsinchiang, Keng & Kao 2689; Toseigun, Maihukuhei, Suzuki 21582. HUALIEN: Tienhsiang, van Steenis 20620; Tailuko, Suzuki 16345.
The sepal characters of 'H. acutisepalum' Hayata approach most closely those of the other species of sect. Takasagoya in Taiwan (Spp. 3,9,14); but there is no gap in variation between such plants and those characteristic of H. geminiflorum. Likewise, the plants from the southernmost part of Taiwan ('H. trinervium' Hemsl.) seem distinct in their broader leaves with strong intramarginal vein; but these, too, are linked to typical H. geminiflorum by intermediates.
4b. var. simplicistylum (Hayata) Robson 小雙花金絲桃
Differs from var. geminiflorum as follows:
Dwarfer (ca. 0.3-0.4 m tall), more erect shrub; leaves similar to var. geminiflorum sen. Str. Rather than 'H. trinervium' (i. e., relatively narrow); axillary flowers and flowering branches from up to 10 pairs of nodes, with flower buds subacute to rounded; ovary ca. 4 mm long, with styles 1-1.3(1.5) times as long; capsule 5-8 mm long, 4-5.5 mm broad, cylindric-ellipsoid to narrowly ovoid-conic; seeds 0.6-1.2 mm long.
Endemic to central and northern Taiwan. Exposed stony ground (mountain slopes, roadsides) at higher altitudes than var. geminiflorum (1,500-1,800 m).
ILAN: Inter Kinyan et Piyahau, Suzuki 6375. TAICHUNG: Lakulaku, Sasaki s. n. 1923. NANTOU: Nengkaoshan, Kawakami & Mori 4507; Hoshe, Huang 4084. CHIAYI: Mt. Morrison, Sasaki s. n. 1935.
Var. simplicistylum is apparently an upland derivative of var. geminiflorum. Although tending to be smaller in all parts and more erect, there is a certain overlap in character variation between it and the typical variety that prevents their recognition as separate species. The relative style length and fruit shape, however, are usually diagnostic.
双花金丝桃（原亚种） Hypericum geminiflerum Hemsl. subp. geminiflorum
灌木，高0.5-1.5米，有常为开张及下垂的枝条。茎幼时具4 纵线棱及两侧压扁，最后具2纵线棱至圆柱形；节间长0.9-3.5厘米，短于叶。叶近无柄；叶片长圆形或长圆状披针形至椭圆形或卵形，长1.8-4.5厘米，宽0.6-2.2厘米，先端锐尖至钝形或圆形而具小尖突，基部宽至狭的楔形，边缘增厚，上面绿色，下面淡绿但不呈苍白色，主侧脉1-2对，上方1对有时形成明显的近边缘脉，中脉有4-9条羽状分枝，第三级脉网模糊或不可见，近边缘腺体密生，叶片腺体点状且有时向上突起。花序有1-2(-3)花，在茎顶及自其下至14节内生出的单一或成对的短侧枝上顶生，花梗长3-4 毫米；小苞片退化，凋落。花直径2-3厘米，星状；花一蕾卵珠形，先端锐尖至钝形。萼片分离或稍合生，覆瓦状排列，宽卵形或三角状卵形或近圆形至长圆状披针形，等大或近等大，长1-2毫米，宽1-2毫米，先端近锐尖至圆形，具1-5脉，小脉不分枝，中脉不明显，腺体大多为线形。花瓣亮黄色或稀为白色，无红脉纹或红晕，开张，倒卵形，长0.9-1.5厘米，宽0,5-0.7厘米，小尖突消失或无。雄蕊5束，每束有雄蕊5-11枚，最长者长0.6-1厘米，长约为花瓣的7/10。子房多少呈狭椭圆形，长2.5-3.5毫米；花柱长4-6(-7)毫米，长约为子房的1.3-2倍，多少柔弱；柱头头状至椭圆形或圆柱形。蒴果狭圆柱形至圆柱状圆锥形，长0.5-1.1厘米，宽0.3-0.55厘米。种子深红褐色，狭圆柱形或狭椭圆状至纺锤形，长0.6-1.5毫米，有狭的龙骨状突起和多少伸长的顶端附属物，或一侧多少有宽翅，表面有浅的线状网纹。花期5-6月，果期9-12月。
产我国台湾中部及南部（高雄、屏东、台东、花莲、宜兰等地）。生于开旷多石地，海拔 300-1200米。菲律宾（吕宋）也有。模式标本采自台湾高雄。
