Abstract

The genus Swertia(Gentianaceae) in Taiwan is revised based on morphological study.Four species, namely S. arisanensis Hayata, S. macrosperma (C. B. Clarke) C. B. Clarke (syn. S. randaiensis Hayata), S. shintenensis Hayata, and S. tozanensis Hayata, are recognized. By detailed comparison of type specimens and filed investigation, S. matsudae Satake, which was previously treated as distinct, is now reduced to the synonymy under S. tozanensis Hayata. Nectaries on coroll-lobes are the most important characters in separating the Taiwanese taxa. Habit, calyx-lobe, seed number per capsule, and seed morphology also display interspecific variation and provide valuable taxonomic significance. A key to the taxa along with descriptions, illustrations, and taxonomic notes are provided.

中文摘要

依據台灣植物誌( Liu ＆ Kuo, 1978)的記載，台灣產當藥屬植物共有五個分類群，然近年來陸續有台灣及大陸之學者重新對本屬植物予以分類處理，各方之分類研究結果頗不一致，顯示仍有深入研究之必要。本文針對台灣產之當藥屬植物進行詳盡的分類研究，研究結果將台灣產的本屬植物處理為四的分類群。其中將細葉當藥(S. matsudae Satake)併入高山當藥(S. tozanensis Hayata)處理為同種，依循Ho et al.(1988)之意見將巒大當藥(S. randaiensis Hayata)併入大籽當藥(S. macrosperma(C. B. Clarke) C. B. Clarke)，並將新店當藥(S. shintenensis Hayata)處理為種的階級。 研究結果顯示花冠裂片上的腺體形態及位置為區分台灣產當藥屬植物最主要的特徵，另外，植物的習性、萼片形態以及種子的數目及形態，亦可作為有效的分類特徵。本文並提供種之檢索表，各種之描述、繪圖及分類註釋。

Keyword: Gentianaceae, Revision, Swertia, Taiwan, Taxonomy