わが国の各地をはじめ、北半球に広く分布しています。山地や草原に生え、高さは5〜20センチになります。茎には毛があって直立し、長楕円形の葉は対生します。5月から8月ごろ、小さな白色の5弁花を咲かせます。和名は、大きな夜具を意味します。別名で「ひめたがそでそう(姫誰が袖草)」とも呼ばれます。中国語では「种阜草(zhong fu cao)」です。
ナデシコ科オオヤマフスマ属の多年草で、学名は Moehringia lateriflora。英名は Grove sandwort。
The Grove sandwort (Moehringia lateriflora) belongs to Caryophyllaceae (the Carnation family). It is a perennial herb that is native throughout Japan and the Northern Hemisphere. This herb grows in mountain or grasslands, and can reach 5-20 cm in height. The stems are erect, hairy, and the leaves are oblong and opposite. The small white flowers bloom from May to August. The Japanese name means big bedding. It is also known as "Hime-tagasode-so" in Japan. It is called "种阜草" (zhong fu cao) in Chinese.