Caltha sinogracilis W. T. Wang

Plants small, glabrous. Stems more than 4 cm tall, to 10 cm at fruiting, ca. 1 mm in diam., simple to 7-branched. Leaves all basal, long petiolate; petiole 3--5 cm; leaf blade orbicular-reniform or reniform-cordate, 1--1.7 × 1.2--3.5 cm, herbaceous, base deeply cordate, margin crenate or dentate basally, apex rounded. Flower solitary, terminal, ca. 2 cm in diam. Pedicels 3--4 cm. Sepals 5, yellow, rarely red, narrowly elliptic, ca. 1.4 cm × 4.5 mm, apex rounded. Stamens ca. 3 mm; anthers oblong, ca. 1 mm. Follicles 5--10, sessile; persistent style ca. 0.8 mm. Seeds dark brown, narrowly ellipsoid-globose, ca. 1.5 mm.

SE Xizang, NW Yunnan.

* Grasslands, by streams; 3200--4100 m.

Caltha gracilis Handel-Mazzetti (1923), not Nakai (1922); C. rubriflora B. L. Burtt & Lauener; C. sinogracilis f. rubriflora (B. L. Burtt & & Lauener) W. T. Wang.

Caltha sinogracilis is close relative of Caltha palustris, but differs from the latter in its leaves all basal (vs. basal and cauline), flower solitary (vs. 3-5), terminal (vs. complex monochasium).

Caltha sinogracilis is occurring in SE Xizang, NW Yunnan of China.

Plants small, glabrous. Stems more than 4 cm tall, to 10 cm at fruiting, ca. 1 mm in diameter, simple to 7-branched. Leaves all basal, long petiolate; petiole 3-5 cm long; leaf blade orbicular-reniform or reniform-cordate, 1-2 cm long, 1.2-3.5 cm wide, herbaceous, base deeply cordate, margin crenate or dentate basally, apex rounded. Flower solitary, terminal, ca. 2 cm in diameter. Pedicels 3-4 cm long. Sepals 5, yellow, rarely red, narrowly elliptic, ca. 1.4 cm long, 4.5 mm wide, apex rounded. Stamens ca. 3 mm; anthers oblong, ca. 1 mm. Follicles 5-10, sessile; persistent style ca. 0.8 mm. Seeds dark brown, narrowly ellipsoid-globose, ca. 1.5 mm.

Growing in grasslands, by streams; 3200-4100 m.

Caltha sinogracilis là một loài thực vật có hoa trong họ Mao lương. Loài này được W.T.Wang mô tả khoa học đầu tiên năm 1965.

细茎驴蹄草（学名：Caltha sinogracilis）为毛茛科驴蹄草属下的一个种。