1	Inflorescences terminal, erect or slightly curved to pendulous; ovary semi-inferior; stamens usually shorter than petals.		(2)
+	Inflorescences axillary, rarely terminal, erect; ovary superior or semi-inferior; stamens usually longer than petals, sometimes shorter.		(5)
2 (1)	Petals reflexed at anthesis; inflorescences erect; leaf blade narrowly lanceolate, distal margin 4-8-glandular dentate on both sides, secondary veins in 6-8 pairs		4 I. amoena
+	Petals erect at anthesis; inflorescences erect or slightly curved to pendulous; leaf blade usually elliptic to broadly so, ovate, obovate, or rarely lanceolate or oblanceolate, margin serrate or dentate with more than 10 teeth on both sides, secondary veins in 4-6 pairs.		(3)
3 (2)	Leaves often crowded at apex of branchlets, subclustered, leaf blade margin glandular dentate; inflorescences erect; petals triangular-lanceolate		1 I. riparia
+	Leaves remotely alternate on branchlets, leaf blade margin rather curved spinose serrate or crenate-dentate; inflorescences nodding to pendulous; petals linear-lanceolate.		(4)
4 (3)	Leaf blade elliptic or ovate, thinly leathery, margin spinose serrate; calyx and pedicels puberulous		2 I. yunnanensis
+	Leaf blade elliptic-oblong or broadly elliptic to orbicular, thickly leathery, margin laxly spinose dentate; calyx and pedicels glabrous		3 I. ilicifolia
5 (1)	Ovary semi-inferior; stamens shorter than or subequaling petals.		(6)
+	Ovary superior; stamens longer than petals.		(7)
6 (5)	Petals reflexed at anthesis; filaments and ovary glabrous; leaf blade broadly ovate to broadly elliptic, glabrous on both surfaces		5 I. macrophylla
+	Petals erect at anthesis; filaments and ovary puberulous; leaf blade oblong or oblong-elliptic, barbellate at vein axils abaxially		6 I. kiukiangensis
7 (5)	Leaf blade thickly leathery.		(8)
+	Leaf blade thinly leathery, papery, or membranous.		(11)
8 (7)	Leaf blade glabrous on both surfaces, margin remotely coarsely dentate or subentire		10 I. oldhamii
+	Leaf blade sparsely glandular or sparsely or densely glandular punctate on both surfaces, margin moderately to densely serrate or crenate.		(9)
9 (8)	Branchlets, inflorescence rachis, pedicels, and calyx glandular; leaf blade sparsely glandular abaxially		7 I. glutinosa
+	Branchlets glabrous; inflorescence rachis, pedicels, and calyx puberulous; leaf blade glandular punctate on both surfaces.		(10)
10 (9)	Leaf blade elliptic or oblong-obovate, ca. 13 × 3-5 cm, apex acute or shortly so; petiole stout, 1.5-2.5 cm		8 I. coriacea
+	Leaf blade oblong or oblong-elliptic, 5.5-7 × 1.7-2.5 cm, apex rounded or obtuse; petiole slender, to 0.7 cm		9 I. yangchunensis
11 (7)	Leaf blade papery or membranous, hairy on both surfaces or at least barbellate at vein axils.		(12)
+	Leaf blade thinly leathery, glabrous on both surfaces.		(13)
12 (11)	Branchlets usually glabrous; inflorescence rachis and pedicels glabrous; leaf blade lanceolate or oblong-lanceolate, membranous or thinly papery, base cuneate or rarely obtuse, margin ± crenulate-serrate or repand, rarely entire		15 I. parviflora
+	Branchlets densely pubescent; inflorescence rachis and pedicels villous; leaf blade elliptic to oblong-elliptic, papery, base rounded to obtuse, margin serrulate to subentire		14 I. indochinensis
13 (11)	Leaf blade narrowly lanceolate, secondary veins in ca. 9 pairs, margin entire proximally, remotely glandular mucronulate in distal 1/3-1/2, apex acuminate, glandular mucronulate; filaments glabrous		11 I. kwangsiensis
+	Leaf blade oblong to ovate-elliptic or obovate, secondary veins in 5-7 pairs, margin proximally shallowly crenate or conspicuously and densely serrulate, distally obscurely crenate-dentate, rarely repand or subentire, apex acute, not mucronulate; filaments pilose.		(14)
14 (13)	Leaf blade obovate or ovate-elliptic, secondary veins in 4 or 5 pairs, base cuneate, margin shallowly crenate, rarely subentire; bracts linear-subulate, shorter than pedicels		12 I. chinensis
+	Leaf blade oblong, rarely elliptic, secondary veins in 5-7 pairs, base rounded or obtuse-rounded, margin conspicuously densely serrulate; bracts leaflike, much longer than pedicels		13 I. omeiensis