1	Plants perennial		(2)
+	Plants annual		(6)
2 (1)	Base of corolla tube not constricted		(3)
+	Base of corolla tube constricted		1 Arnebia guttata
3 (2)	Inflorescence globose or broader than long. Leaves faintly nerved		(4)
+	Inflorescence much broader than long. Leaves distinctly nerved		(5)
4 (3)	Plants up to 15 cm tall, eglandular. Stem arising from center of leaves. Leaves 3-5 mm broad		3 Arnebia inconspicua
+	Plants up to 40 cm tall, glandulose, Stem lateral. Leaves 5-11 mm broad		2 Arnebia euchroma
5 (3)	Inflorescence interrupted. Bracts shorter, not exceeding the calyces in the upper half of inflorescence		5 Arnebia speciosa
+	Inflorescence not interrupted. Bracts longer, exceeding the calyces throughout the inflorescence length		4 Arnebia benthamii
6 (1)	Corolla lobes fimbriate to lobed at the apex		6 Arnebia fimbriopetala
+	Corolla lobes entire		(7)
7 (6)	Style 2-fld or entire. Stigma bibbed or entire		(8)
+	Style doubly 2-fid at apex		(10)
8 (7)	Calyx with prominent midrib and veins, dilated at base, lobes obtuse		7 Arnebia linearifolia
+	Calyx without prominent midrib or veins, barely dilated at base, lobes acute		(9)
9 (8)	Plants densely hispid. Leaves lanceolate. Corolla yellow, 10-15 mm long; limb 4-5 mm long, not spotted		11 Arnebia hispidissima
+	Plants not densely hispid. Leaves broad lanceolate to oblanceolate. Corolla yellow-orange, 20- 25 mm long; limb 15-17 mm long, with 5 purple-brown spots		10 Arnebia griffithii
10 (7)	Corolla 20-37 mm long, limb more than 10 mm broad, with 5 purple-brown spots		9 Arnebia grandiflora
+	Corolla less than 20 mm long, limb less than 10 mm broad, not spotted or rarely so		8 Arnebia decumbens