あさがおがらくさ (朝顔柄草) [Index] [Back] わが国の九州南部から南西諸島、それに台湾や中国、東南アジアに分布しています。乾燥した草原や荒地、道ばたなどに生え、地面を匍匐して横に広がります。茎は長さ２０〜７０センチに伸び、枝先を斜上させます。葉や茎には灰褐色から銹色の絹毛があります。葉は狭長楕円形から広楕円形で、全縁です。ほぼ一年中、枝先や葉腋に集散花序をだし、淡紫色から青色の花を咲かせます。花冠は直径７〜１０ミリで、先端は５浅裂します。台湾華語では「土丁桂」、中国語では「土丁桂（tu ding gui）」と呼ばれます。 ヒルガオ科アサガオガラクサ属の多年草で、学名は Evolvulus alsinoides。英名は Dwarf morning glory、Slender dwarf morning glory。 The Dwarf morning glory (Evolvulus alsinoides) belongs to Convolvulaceae (the Bindweed family). It is a perennial herb that is distributed from southern Kyushu to the Nansei Islands in Japan, as well as in Taiwan, China, and Southeast Asia. It grows in dry grasslands, wastelands, and along roadsides, creeping along the ground and spreading laterally. The stems grow to a length of 20-70 cm, with the tips of the branches pointing obliquely upward. The leaves and stems are covered with grayish-brown to rust-colored silky hairs. The leaves are narrowly to broadly elliptical and have entire margins. It produces corymbs of pale purple to blue flowers at the branch tips and in the leaf axils almost year-round. The corolla is 7-10 mm in diameter and has five shallow lobes at the tip. In Taiwanese Chinese, it is called "土丁桂", and "土丁桂" (tu ding gui" in Chinese. 茨城県つくば市「つくば実験植物園」にて、2026年03月28日撮影。 Shu Suehiro shu@botanic.jp