别名：川上悬钩子;

科名：蔷薇科 Rosaceae

属名：悬钩子属 Rubus

《中国植物志》第37卷195页
  167.桑叶悬钩子（台湾植物志）
  Rubus kawakamii Hayata in Journ. Coll. Scl. Univ. Tokyo. 30 (1): 91. 1911: Liu et Su in Fl. Taiwan 3: 115. 1977.
  灌木，高达1.5米；枝圆柱形，幼时具绒毛状毛，老时脱落无毛，疏生皮刺。单叶，非革质，长圆形或卵状长圆形，长6-10厘米，宽2.5-4.5厘米，顶端渐尖，基部宽楔形至圆形，上面无毛，下面幼时沿叶脉具绒毛状毛，老时无毛或沿叶脉有少数毛，边缘不分裂，具不整齐锐锯齿，叶脉7-10对，在上面微下陷，下面突起；叶柄细，长1-2厘米，幼时被绒毛状毛，老时近无毛，无或有稀疏小皮刺；托叶长圆形，长6-8毫米，宽2-3毫米，稍具锯齿，外面被柔毛，早落。花常5-9朵成顶生伞房状总状花序；总花梗和花梗被绒毛状毛；花梗长1.5-2.5厘米；苞片与托叶相似；花开展时直径1-1.3厘米；花萼钟形，外面密被绒毛，具小针刺或几无刺；萼片三角状卵形，长5-6毫米，顶端急尖，常不分裂，花后直立开展；雄蕊很多，花丝线形，近基部稍宽扁；雌蕊多数，无毛。果实半球形，无毛；核肾形，较平滑或微具浅皱纹。花期6-7月，果期8月。
  产我国台湾全省，自中海拔至2500米地区。
  本种和木莓R. swinhoei Hance相近缘，但本种叶片无毛，仅于下面沿叶脉稍有毛；花成伞房状总状花序，无腺毛。
形态特征：灌木，高达1．5米；枝圆柱形，幼时具绒毛状毛，老时脱落无毛，疏生皮刺。单叶，非革 质，长圆形或卵状长圆形，长6—10厘米，宽2．5—4．5厘米，顶端渐尖，基部宽楔形至圆形， 上面无毛，下面幼时沿叶脉具绒毛状毛，老时无毛或沿叶脉有少数毛，边缘不分裂，具不整 齐锐锯齿，叶脉7—10对，在上面微下陷，下面突起；叶柄细，长1—2厘米，幼时被绒毛状 毛，老时近无毛，无或有稀疏小皮刺；托叶长圆形，长6—8毫米，宽2—3毫米，稍具锯齿， 外面被柔毛，早落。花常5—9朵成顶生伞房状总状花序；总花梗和花梗被绒毛状毛；花梗 长1．5—2．5厘米；苞片与托叶相似；花开展时直径1—1．3厘米；花萼钟形，外面密被绒毛， 具小针刺或几无刺；萼片三角状卵形， 长5—6毫米，顶端急尖，常不分裂，花后直立开展； 雄蕊很多，花丝线形，近基部稍宽扁；雌蕊多数，无毛。果实半球形，无毛；核肾形，较平滑 或微具浅皱纹。 花期6一7月，果期8月。
产地分布：产我国台湾全省，自中海拔至2500米地区。
本种提示：本种和木莓R．Swinhoei Hance：相近缘，但本种叶片无毛，仅于下面沿叶脉稍有毛；花 成伞房状总状花序，无腺毛．
参考文献：Rubus kawakamii Hayata in Journ．Coil．Sci．Univ。Tokyo．30(1)：91．1911；Liuct Su in F1．Taiwan 3：115．1977．
亚组概述：Subsect；Sozostyli；(Focke)yu et lu，植物分类学报20(4)：461．1982．-Sect．Sozostyli Focke，Bibl．Bot。—72(1):42.1910 et 83:22. 1914. 本亚组有下列17种。

《Flora of China》 Vol. 9 (2003)
Rubus kawakamii  Hayata
桑叶悬钩子   sang ye xuan gou zi
Shrubs erect, to 1.5 m tall. Branchlets brownish to reddish brown, terete, tomentose-villous when young, later glabrate, with few small prickles. Leaves simple; petiole 1–2 cm, slender, tomentose-villous when young, glabrate in age, unarmed or with sparse, small prickles; stipules caducous, oblong, 6–10 × 2–4 mm, soft hairy, margin entire or with a few teeth; blade oblong or ovate-oblong, 6–10 × 2.5–5 cm, lateral veins 7–10 pairs, midvein and veins raised abaxially, slightly impressed adaxially, papery, abaxially slightly tomentose-villous along veins, glabrate in age, adaxially glabrous but hirsute along midvein, base broadly cuneate to subcordate, margin undivided, unevenly sharply serrate, apex long acuminate. Inflorescences terminal, corymbose racemes, 3–6 cm, 5–9-flowered; rachis and pedicels tomentose-villous, with small prickles, with few to many shortly stalked glands; bracts narrowly oblong to ovate, 6–9 × 2–4 mm, soft hairy, margin apically divided or with few teeth along margin. Pedicel 1.5–2.5 cm. Flowers 1–1.5 cm in diam. Calyx campanulate, abaxially tomentose, unarmed or with sparse, minute needle-like prickles, sometimes with shortly stalked glands; sepals erect-spreading after anthesis, triangular-ovate, 5–8 × 2–3 mm, margin usually undivided, apex acute. Petals obovate, 5–7 × 5–6 mm, both surfaces soft hairy, base shortly clawed. Stamens numerous, shorter than petals; filaments linear, broadened and flattened basally. Pistils slightly shorter than or nearly as long as stamens; style and ovary glabrous. Aggregate fruit subglobose, 7–10 mm, glabrous; pyrenes reniform, smooth or somewhat shallowly rugose. Fl. Jun–Jul, fr. Aug–Sep. 2n = 28*.
Mountains; 2000--2800 m. C Taiwan.