Oenanthe thomsonii C. B. Clarke (Umbelliferae) a Newly Recorded Plant in Taiwan

台灣的繖形科新記錄－－多裂葉水芹菜

Oenanthe (Umbelliferae), comprising about 25-30 species in Africa, Asia, Europe, North America. Two species were recorded in the 2nd edition of Flora of Taiwan. In the course of our botanical inventory, Oenanthe thomsonii C. B. Clarke, heretofore unknown in Taiwan, was collected from northern part of the island. O. thomsonii C. B. Clarke is easily distinguished from other congeners by leaves 3-4-(- 5) pinnate and ultimate segments short linear, 2-3 × 1-2 mm. In this report we provide a description and colored photographs taken from the wild to aid identification. 水芹菜屬為繖形科的一屬，全部約有25-30種主要分佈於非洲、亞洲、歐洲及北美洲，台灣植物誌紀錄有2種，本報告提出在台灣北部植物調查發現之另一新紀錄植物－－多裂葉水芹菜；該植物的葉3-4回羽狀分裂，稀為5回羽狀分裂，末回裂片線形，長2-3公釐，寬1-2公釐，可明顯與台灣產本屬其他物種區別。本文提供該種的形態描述與彩色圖片。