1	Verticillasters 2(-4, rarely more)-flowered, widely spaced; floral leaves similar to stem leaves; fertile branches (only) erect to ascending.		(2)
+	Verticillasters 6- or more flowered, close together; floral leaves unlike stem leaves (except in A. linearifolia); plants erect, rarely trailing		(5)
2 (1)	Base of corolla tube not villous annulate inside; leaf base cordate to subtruncate		1 Ajuga lobata
+	Base of corolla tube villous annulate inside; leaf base cuneate to subtruncate, decurrent.		(3)
3 (2)	Leaves spatulate, 2-3 × 4-6 mm		2 Ajuga pygmaea
+	Leaves ovate to oblong, more than 10 mm wide.		(4)
4 (3)	Leaves 3-5.3 × 2.5-3.8 cm, ovate to ovate-oblong, basally cuneate to subtruncate, slightly decurrent		3 Ajuga sciaphila
+	Leaves 2-3.4 × 1.2-2.3 cm, oblong to ovate-oblong, basally cuneate to decurrent		4 Ajuga nubigena
5 (1)	Floral leaves longer than flowers, whitish yellow, white, or purple		5 Ajuga lupulina
+	Floral leaves equal to or slightly shorter than flowers, rarely longer, green or purplish		(6)
6 (5)	Corolla tube (1.5–)2–3 cm, upper lip 2-lobed		6 Ajuga ovalifolia
+	Corolla tube less than 1.6 cm, rarely to 2 cm, upper lip shallowly 2-lobed		(7)
7 (6)	Floral and stem leaves similar, of 1 color; stem leaves linear to linear-lanceolate		18 Ajuga linearifolia
+	Floral and stem leaves dissimilar; stem leaves of other shapes		(8)
8 (7)	Corolla tube erect to slightly curved, not saccate or bent above annulus of hairs		(9)
+	Corolla tube slightly swollen, shallowly saccate to bent above annulus of hairs		(14)
9 (8)	Calyx ciliate along veins and teeth margin, villous to puberulent apically, glabrous basally, or subglabrous throughout		(10)
+	Calyx strigose, villous, or lanate-villous throughout, especially on teeth		(12)
10 (9)	Stems 25–40 cm tall, purplish red or greenish purple, glabrous, gray villous only on younger parts; leaves ovate-oblong to narrowly oblong, 4–7.5?×?3.2–4 cm, irregularly double dentate		7 Ajuga ciliata
+	Stems less than 20 cm tall, sometimes to 30 cm, not brightly colored, densely gray pubescent to gray villous; leaves ovate to lanceolate-oblong, less than 3.2 cm wide, margin repand		(11)
11 (10)	Inflorescences 1–3 cm; floral leaves usually shorter than flowers; calyx white villous on teeth		9 Ajuga campylanthoides
+	Inflorescences ca. 6 cm; floral leaves much longer than flowers; calyx ciliate along veins and apical teeth margin		11 Ajuga forrestii
12 (9)	Calyx strigose; corolla tube slightly curved; stamens nearly included; plants subprostrate, basally stoloniferous		10 Ajuga campylantha
+	Calyx villous or lanate-villous; corolla tube straight; stamens slightly exserted; plants erect or stoloniferous		(13)
13 (12)	Stems erect, unbranched, 6–21 cm tall, densely gray lanate or silky		8 Ajuga multiflora
+	Plants with stolons and erect fertile stems ca. 10 cm tall, gray villous or lanate-villous		12 Ajuga bracteosa
14 (8)	Calyx teeth lanceolate to lanceolate-triangular; plants spreading ascending or with stolons		13 Ajuga pantantha
+	Calyx teeth narrowly triangular to broadly ovate; plants erect, sometimes trailing-ascending		(15)
15 (14)	Corolla 6–8(–9) mm; calyx teeth ovate to ovate-triangular; stamens exserted ca. 1/2 their length		(16)
+	Corolla more than 8 mm; calyx teeth narrowly or short triangular; stamens exserted 1/4–1/3 their length		(17)
16 (15)	Corolla white, upper lip shorter than lateral lobes of lower lip; calyx teeth ovate-triangular		16 Ajuga dictyocarpa
+	Corolla blue, blue-purple, or purple, upper lip nearly as long as lateral lobes of lower lip; calyx teeth ovate to broadly ovate		17 Ajuga macrosperma
17 (15)	Leaves spatulate to suboblong; plants prostrate, with basal leaves at anthesis		14 Ajuga decumbens
+	Leaves broadly oblong to obovate-elliptic; plants erect or rarely prostrate, branched at base, without basal leaves at anthesis		15 Ajuga nipponensis