福建新記錄茜草科植物——圓莖鈕扣草

Diodia teres Walt. (Rubiaceae), a Newly Recorded Weed in Fujian

「圓莖鈕扣草」原產美洲熱帶及亞熱帶，本文報導其歸化於福建省金門縣，為福建省新紀錄植物。它和同屬植物「雙角草」形態相似，但圓莖鈕扣草具有四至八條撕裂狀托葉，蒴果具四枚宿存萼片等特徵易與之區分。本文提供圓莖鈕扣草的形態描述和線繪圖，並對產於臺灣和福建「雙角草屬」的兩個種製作檢索表以供區分鑑定。

Diodia teres Walt., an annual herb native to tropical and subtropical America, is found to be a newly recorded weed in Fujian. It is similar to D. virginiana L. except that it is characterized by the 4~8 fimbriate stipules and 4 persistent sepals in the capsule. The morphological description and illustration of D. teres and a key of Diodia in Taiwan and Fujian are provided in the present work.