1	Leaves pinnate, with very small lateral leaflets and much longer, simple, terminal leaflets		7 Clematis aspleniifola
+	Leaves ternate to pinnate with ± equal leaflets		(2)
2 (1)	Leaflets linear-lanceolate to narrowly ovate, never cordate at base, sometimes distinctly lobed with entire lobes		(3)
+	Leaflets with cordate base or ± broadly ovate, grossly dentate, rarely entire or lobed with a few grossly dentate lobes		(6)
3 (2)	Flowers single on long pedicels. Corolla-l ike sepals yellow, at least 3 cm long		(4)
+	Flowers in panicles or few-flowered fascicles, not distinctly corolla-l ike, sepals white or pale yellow, less than 3 cm		(5)
4 (3)	Filaments dilated, petaloid, but always bearing fertile anthers		1 Clematis robertsiana
+	Petaloid staminodes present		10 Clematis alpina var. sibirica
5 (3)	Filaments longer than anthers		8 Clematis graveolens
+	Filaments shorter than anthers		9 Clematis orientalis
6 (2)	Leaves ternate. Flowers single or in fascicles on long pedicels		(7)
+	Leaves pinnate or bi-pinnate		(8)
7 (6)	Sepals white to yellowish-white, obtuse to subacute, oblong to ovovate. Anthers glabrous		2 Clematis montana
+	Sepals violet outside, narrower, acute to sub-acute. Anthers slightly bearded		11 Clematis barbellata
8 (6)	Leaflets leathery, ± riged, often shiny on the upper surface. Flowers densely paniculate		3 Clematis gouriana
+	Leaflets neither leathery nor rigid		(9)
9 (8)	Sepals 6-8 (-10) mm long, horizontally spreading		4 Clematis grata
+	Sepals 10-20 mm long-erect, curved backwards at the tips		(10)
10 (9)	Sepals with ± parallel ribs, 15-20 mm long		5 Clematis buchananiana
+	Sepals without ribs, 10-12 mm long		6 Clematis connata