Flaveria linearis Lag. (Asteraceae), a Newly Naturalized Plant in Taiwan

Flaveria linearis Lag. (Asteraceae), a shrub native to southern North America and Central America, has naturalized to the coast of Shenkang Hsiang, Changhua County, Taiwan. A taxonomic treatment, distribution and habitat, line drawings, color photographs and voucher specimens are provided to aid in identification of this alien plant. A detailed comparison between F. linearis and the closely related species, F. bidentis (L.) Kuntze, reported earlier as a naturalized species in Taiwan, is also provided.線葉黃頂菊 (Flaveria linearis Lag.) 原產北美洲南部及中美洲，近年來已歸化於台灣中部彰化縣伸港鄉沿海一帶。本文描述其形態特徵、地理分布及生育地環境，並提供彩色圖片、線繪圖與引證標本以資辨識，此外亦列表與先前已歸化本地的黃頂菊 (F. bidentis (L.) Kuntze) 作比較。作者等於1999年即已發現線葉黃頂菊族群，2010年及2011年再進行調查時發現其野外族群穩定成長