Clematis longisepala Hayata; C. tozanensis Hayata; C. yingtzulinia S. S. Ying.

Vines woody. Branches shallowly 8--15-grooved, glabrous. Leaves pinnate, 5-foliolate, or ternate, glabrous; petiole 3.5--9.4 cm, base strongly dilated and connate to basally widened part of opposite petiole; leaflet blades ovate to narrowly so, 3--22 × 1.6--12 cm, papery, base rounded to subcordate, margin entire, apex acute to acuminate; basal veins abaxially ± prominent to nearly flat. Cymes axillary, (1--)3--8-flowered, glabrous; peduncle 1.5--6 cm; bracts petiolate, narrowly ovate to elliptic, 1.8--5.5 cm. Flowers 3--6 cm in diam. Pedicel 5.5--12 cm, glabrous. Sepals 4--6, dark purple, spreading, narrowly oblong, linear, or lanceolate-oblong, 1.8--3 × 0.4--0.8 cm, abaxially brown velutinous, adaxially glabrous, apex acute. Stamens unequal in length, outer ones 1--2.2 cm, inner ones 6--12 mm, glabrous; anthers narrowly oblong to linear, 2--3.5 mm, apex with a 0.5--1 mm apicula. Ovaries pubescent. Style 6--9 mm, densely villous. Achenes narrowly elliptic, 4--5 × 2--2.8 mm, sparsely appressed pubescent; persistent style 4--6 cm, plumose. Fl. Aug--Oct, fr. Oct--Jan.

Forest margins, slopes, along streams, beaches; below 100--2800 m. Taiwan [Japan (Ryukyu Islands), N Vietnam].