重新確認臺灣產杜鵑花屬植物——丁香杜鵑

Rhododendron farrerae Tate ex Sweet (Ericaceae), a Reconfirmed Species in Taiwan

日本學者Kawakamii早在1910年記錄丁香杜鵑（Rhododendron farrerae）分布於臺灣。此段期間，由於缺乏足夠文獻與標本，本植物一直認定為大武杜鵑（R. tashiroi）並於1998年從臺灣植物誌刪除。經查閱貯存之標本與資料，可以確認丁香杜鵑確實分布於臺灣南部中央山脈南端，從北大武山至台東縣達仁鄉。本種與大武杜鵑及守城滿山紅最主要的區別在於本種花頂生於枝條且僅1朵花，大武杜鵑及守城滿山紅則2-3朵花叢生於枝條。本文提供丁香杜鵑詳細的分類處理、形態描述、分布圖、手繪圖、照片及3種近似種形態比較表，以供分類參考。

Rhododendron farrerae Tate ex Sweet was first recorded in Taiwan by Kawakami in 1910. Since then, this species has been grouped with R. tashiroi Maxim. due to insufficient reports and specimens, and was eliminated from Flora of Taiwan in 1998. By examining all the specimens preserved in Taiwan herbaria and documents, we confirm that the native population of R. farrerae is actually distributed in southern Taiwan, ranging from Peitawushan to Tajen Township, in the southern part of the Central Mountain Range. The diagnostic character distinguishing R. farrerae from R. tashiroi and R. mariesii Hemsl. & E. H. Wils. is that R. tashiroi and R. mariesii bear 2-3 flowers from each bud at anthesis; in contrast, R. farrerae bears only one flower during the flowering period. We provide in this paper a detailed taxonomic treatment, morphological description, distribution map, line drawing, and a comparison table of these three species of Taiwan, together with photographs.