1	Internodes shorter than the leaves		1 Galium ceratophylloides
+	Internodes longer than the leaves		(2)
2 (1)	Fruit glabrous or granulate		(3)
+	Fruit hairy		(14)
3 (2)	Fruiting pedicel decurved. Fruit 3-5 mm in diameter		(4)
+	Fruiting pedicel ± straight. Fruit less than 3 mm in diameter		(5)
4 (3)	Plants glabrous. Fruit smooth or rough but not granulate, often with white sunken hair-like raphide crystals		2 Galium kurramensis
+	Plants scabrid Fruit granulate, without sunken hair-like raphide crystals		3 Galium tricornutum
5 (3)	Flowering branches leafy (leaves of flowering branches much smaller than the vegetative leaves)		(6)
+	Flowering branches not leafy		(11)
6 (5)	Inflorescence divaricately branched. Main stem either minutely scabrid, or minutely to strongly scabrid, or angles smooth		(7)
+	Inflorescence not divaricately branched. Main stem glabrous		(9)
7 (6)	Corolla lobes lanceolate, shortly apiculate. Leaf margins recurved, with antrorsely papiliform teeth		4 Galium saturejifolium
+	Corolla lobes ovate, acuminate. Leaves only scabrous above, specially on midrib and margins		(8)
8 (7)	Leaves always in a whorl of 4		24 Galium tetraphyllum
+	Leaves in a whorl of 6-8		23 Galium asperifolium
9 (6)	Fruits glabrous-granulate. Pedicel small, always smaller than flower		20 Galium acutum
+	Fruits papillose with curved setose hairs. Pedicel elongated always larger than flower		(10)
10 (9)	Flowers yellowish brown upon drying. Inflorescence reduced to few flowers. Leaves in approximate whorls of 6, margins scarcely revolute		22 Galium campylotrichum
+	Flowers purplish upon drying. Inflorescence not reduced. Leaves in whorls of 6-8, margins revolute		21 Galium subfalcatum
11 (5)	Leaves elliptic, lanceolate or oblanceolate, usually obtuse		8 Galium spurium
+	Leaves linear, acute or cuspidata		(12)
12 (11)	Inflorescence terminal or subterminal. Pedicel c. 2 mm long. Corolla bright yellow. Stem pubescent-glabrate; leaves 8-10 (-12) in a whorl		9 Galium verum
+	Inflorescence axillary and terminal. Pedicel 3-5 mm long. Corolla usually white. Stem minutely scabrid; leaves 6 in a whorl		(13)
13 (12)	Cymes 5-8 cm long, laxly divaricately branched. Fruit c. 1-1.5 mm across, smooth, mericarps mostly free		10 Galium tenuissimum
+	Cymes 2-3 cm long, forked. Fruit 2-2.5 mm across, covered with white sunken hair like markings, mericarps not free		11 Galium chitralensis
14 (2)	Leaves trinerved beneath		(15)
+	Leaves not trinerved		(17)
15 (14)	Upper surface of the Leaves hairy or pubescent Leaves ovate-obovate or elliptic		(16)
+	Upper surface of the leaves glabrous. Leaves lanceolate		12 Galium boreale
16 (15)	Fruit covered with soft whitish hooked hairs. Leaves 10-30 x 5-15 mm, villous, pubescent beneath		13 Galium elegans
+	Fruit with short compressed hairs. Leaves 6-9 x 3-5 mm, covered on nerves with hooked hairs		7 Galium stewartii
17 (14)	Leaves 4 in a whorl. Fruit covered with dense long woolly straight hairs		14 Galium serpylloides
+	Leaves (4-) 6-8 (-10). Fruit covered with hooked bristles		(18)
18 (17)	Branches filiform. Fruit c. 1 mm in diameter		(19)
+	Branches not filiform. Fruit 2 or more than 2 mm in diameter		(20)
19 (18)	Fruit with few short hooked hairs. Corolla shortly apiculate or muticous		15 Galium decaisnei
+	Fruit covered with long hooked hairs. Corolla lobes acute or cuspidate		16 Galium setaceum
20 (18)	Inflorescence terminal or subterminal		17 Galium asperuloides
+	Inflorescence axillary and terminal		(21)
21 (20)	Bracts foliaceous. lorescence paniculate. Stem and leaves usually laxly covered with long weak hairs		18 Galium hirtiflorum
+	Bracts not foliaceous. Inflorescence 1-3 flowered cyme. Stem and leaves not covered with long, weak hairs		(22)
22 (21)	Inflorescence more than 1-flowered		19 Galium aparine
+	Inflorescence 1-flowered		(23)
23 (22)	Stem unbranched, ± filiform. Leaves linear or narrowly lanceolate		5 Galium pauciflorum
+	Stem branched, quadrangular. Leaves oblanceolate-lanceolate		6 Galium ibicinum