1	Leaves alternate (see also B. X wardii)		1 Buddleja alternifolia
+	Leaves opposite (sometimes apical leaves alternate in B. asiatica).		(2)
2 (1)	Corolla 2.3--3 cm, throat to 9 mm in diam., tube (1.2--)1.7--2.1 cm; fruit a capsule 1--1.6 cm		2 Buddleja colvilei
+	Corolla 2 cm or less, throat to 3.5 mm in diam., tube 1.3 cm or less (but to 1.7 cm in B. lindleyana); fruit a capsule (3--)4--8(--1.2) cm or a globose berry 2--2.5 mm (B. madagascariensis).		(3)
3 (2)	Inflorescences a dense spike with many bracts of which some are longer than flowers		3 Buddleja yunnanensis
+	Inflorescences not a dense spike or if so then only some pairs of bracts among the flowers exceeding them (see B. asiatica and B. crispa).		(4)
4 (3)	Corolla mostly curved, outside covered with a short indumentum; anthers mostly inserted at or below middle of corolla tube (above middle in B. brachystachia); inflorescences usually spicate (thyrsoid in B. brachystachia).		(5)
+	4b. Corolla straight, outside glabrous, partly hairy, or entirely stellate tomentose; anthers inserted at or above middle of corolla tube or if inserted lower to middle of corolla tube then outside glabrous or only partly hairy (B. forestii and B. davidii); inflorescences not spicate or if spicate then corolla tube less than 5 mm (B. asiatica and B. myriantha), or broadly cylindrical and 8--11 X 2--3.2 mm (B. macrostachya), or leaves ± lobed (B. crispa) (see also B. brachystachya).		(7)
5 (4)	Leaf blade 1--3.5 X 0.5--1.7 cm, apex acute to slightly obtuse; inflorescences 1.5--3 X 1.5--2.5 cm; ovary stellate tomentose except glabrous at base		4 Buddleja brachystachya
+	Leaf blade 3--16 X 1.5--7 cm (occasionally smaller), apex acuminate to less often acute (sometimes obtuse in B. curviflora; inflorescences 4--20 X 2--4 cm; ovary glabrous.		(6)
6 (5)	Branchlets terete or occasionally obscurely angular, (1--)2--3 mm in diam. when dry; leaf margin entire to subentire; calyx and corolla outside shortly stellate tomentose to stellate pubescent and with some glandular hairs		5 Buddleja curviflora
+	Branchlets quadrangular to subquadrangular, 1(--2) mm in diam. when dry; leaf margin coarsely sinuate-dentate or entire; calyx and corolla outside pubescent with glandular hairs which may be accompanied by some stellate hairs		6 Buddleja lindleyana
7 (4)	Leaf blade ovate to triangular or narrowly so, base mostly rounded to cordate and abruptly narrowed into petiole; seeds unwinged		7 Buddleja crispa
+	Leaf blade narrowly elliptic to ovate, base mostly cuneate or decurrent but never abruptly narrowed or cordate; seeds winged (unwinged in B. madagascariensis).		(8)
8 (7)	Corolla tube outside glabrous or partly hairy (portion included in the calyx tube always glabrous).		(9)
+	Corolla tube outside entirely stellate tomentose.		(12)
9 (8)	Inflorescences paniculate, rather lax		8 Buddleja delavayi
+	Inflorescences thyrsoid or spiciform, occasionally paniculate in B. forrestii, mostly rather dense.		(10)
10 (9)	Corolla tube broadly cylindrical, 7--11 X (1.2--)2--3.5 mm		9 Buddleja forrestii
+	Corolla tube obconic and to 6.5 mm or narrowly cylindrical and 6--11.5 X ca. 1 mm.		(11)
11 (10)	Corolla tube obconic, 4--6.5 mm; stamens inserted just inside corolla mouth; corolla lilac		10 Buddleja albiflora
+	Corolla tube narrowly cylindrical or nearly so, 6--11.5 mm; stamens inserted at ± middle or near base of corolla tube; corolla white to dark purple (see also B. davidii X B. fallowiana)		11 Buddleja davidii
12 (8)	Corolla tube 2.5--6 mm, if more than 5 mm then mostly over 2 mm wide; inflorescences thyrsoid or spicate (paniculate sometimes in B. nivea).		(13)
+	Corolla tube (6--)7--13.5 mm, if less than 8 mm then mostly less than 2 mm wide; inflorescences paniculate, thyrsoid, or spicate (see also B. davidii).		(17)
13 (12)	Ovary glabrous or scaly.		(14)
+	Ovary stellate tomentose.		(15)
14 (13)	Inflorescences spiciform; lower branches not longer than others; corolla mostly white; leaf blade mostly remotely serrate-dentate		12 Buddleja asiatica
+	Inflorescences almost cylindrical; lower branches exceeding others; corolla mostly purple; leaf blade mostly serrate		13 Buddleja myriantha
15 (13)	Calyx and corolla outside shortly stellate tomentose; calyx lobes not obscured by their indumentum; corolla tube 1--1.3 wide		13 Buddleja myriantha
+	Calyx and corolla outside densely stellate tomentose; calyx lobes often obscured by their indumentum; corolla tube mostly 1.8 mm wide or wider.		(16)
16 (15)	Leaf blade adaxially bullate to rugose; stamens often inserted at middle of corolla tube		14 Buddleja candida
+	Leaf blade adaxially not bullate or rugose; stamens inserted just 1--1.5 mm inside corolla mouth		15 Buddleja nivea
17 (12)	Inflorescences racemose, spiciform, or thyrsoid and calyx lobes acuminate.		(18)
+	Inflorescences paniculate or thyrsoid, if thyrsoid then calyx lobes acute or obtuse.		(19)
18 (17)	Inflorescences racemose or spiciform, continuous and dense or less often interrupted and rather lax; corolla tube mostly broadly cylindrical and at least 2 mm wide; branchlets quadrangular and often 4-winged		16 Buddleja macrostachya
+	Inflorescences thyrsoid, sometimes interrupted; corolla tube cylindrical, 1--1.5 mm wide; branchlets terete		17 Buddleja fallowiana
19 (17)	Inflorescences laxly paniculate; corolla tube 10--13.5 mm, often glabrous just above calyx; calyx lobes acuminate		8 Buddleja delavayi
+	Inflorescences paniculate or thyrsoid, lax or congested; corolla tube 6--10 mm, outside entirely stellate tomentose; calyx lobes acute or obtuse.		(20)
20 (19)	Corolla dark yellow, orange, or salmon; anthers barely included; fruit baccate		19 Buddleja madagascariensis
+	Corolla white to pale purple; anthers with apex at least 1 mm below corolla mouth; fruit capsular.		(21)
21 (20)	Corolla tube 1.2--1.6(--2) mm in diam., inside pilose up to insertion of stamens or up to just inside mouth; leaf blade margin entire or less often serrate, apex acuminate to rarely acute		18 Buddleja paniculata
+	Corolla tube (1.6--)2--2.2 mm in diam., inside densely pilose up to mouth or less often just inside mouth; leaf blade margin entire or sinuate to repand dentate, apex mostly acute to obtuse		20 Buddleja officinalis