Abstract

Emilia praetermissa (Asteraceae), first collected in 1997 in Keelung, has become naturalized in Taiwan and is now a frequent sight in northern part of the island. This species has often been misidentified as Emilia fosbergii, another alien Emilia species commonly seen in central and southern Taiwan. Detailed description, report of chromosome number (2n = 20) and karyotype with a review of relevant cytological literature and a distribution map are provided. Line-drawings as well as color photographs of E. praetermissa and its congeners occurring in Taiwan are presented to aid in identification.

中文摘要

本文提供臺灣北部新歸化植物「粉黃纓絨花」之形態描述、線繪圖、彩色照片與其分布圖，並報導其染色體數與核型分析。粉黃纓絨花的最早採集記錄是1997 年於基隆市，目前已廣泛歸化於宜蘭縣與臺北縣市。臺灣各主要標本館典藏之粉黃纓絨花標本常被錯誤鑑定為中南部常見之紫背草屬另一種植物「纓絨花」。粉黃纓絨花之頭花花冠為極特別之淡黃色或淺橘色，易於與纓絨花之深橘紅色頭花區別之。本文並報導粉黃纓絨花的染色體數（2n = 20）及核型，且回顧相關之染色體細胞學資料。

Keyword: Compositae, Emilia, invasive plant, Taiwan, taxonomy. 菊科、紫背草屬、入侵植物、臺灣、分類學。