Key to species of Galium and to related genera of the Rubieae

1 (1)	Interpetiolar stipules inconspicuous, multifid or fimbriate, not leaflike and not forming whorls with true leaves; corolla funnelform, (4 or)5-lobed; ovary and dry mericarps with hooked trichomes.		Kelloggia (see p. 183)
+	Interpetiolar stipules mostly leaflike and in whorls with true leaves, rarely reduced		(2)
2 (2)	Corolla lobes regularly 5; fruit fleshy, mericarps berrylike, 2(or 1, by non-development), often dispersed together.		Rubia (see p. 305)
+	Corolla lobes usually 4 (rarely 3); fruit dry or leathery, mericarps mostly 2, nearly always separating for dispersal		(3)
3 (2)	Leaves in middle stem region opposite, with stipules reduced or ± leaflike and in whorls of 4 but then always clearly smaller than true leaves		(4)
+	Leaves in middle stem region opposite and with very similar leaflike stipules in whorls of 4-16		(6)
4 (4)	Corolla pink, funnelform, with well-developed tube longer than lobes; fruit smooth Asperula oppositifolia (see p. 78)		(4)
+	Corolla white, rotate, with tube shorter than lobes; fruit with uncinate trichomes		(5)
5 (4)	Perennial herbs; leaves 5-30 × 5-23 mm, obtuse to truncate at base, on petioles 1.5-10 mm; flowers 3-11 in cymes; corolla with 4 lobes.		39 G. paradoxum
+	Annual herbs; leaves 2-12 × 1-4 mm, acute to cuneate at base, subsessile or on short petioles; flowers solitary at each node; corolla mostly with 3 lobes.		16 G. exile
6 (3)	Leaf apex rounded, obtuse, or ± blunt, never acute or with a hyaline mucro; leaves in whorls of 4-6, linear to broadly oblong, 1-nerved, dried blackening; ripe mericarps globose, didymous and only with a short zone of contact, glabrous; corolla cup-shaped to slightly campanulate, 3- or 4-merous		(7)
+	Leaf apex mostly ± acute, often with a hyaline mucro; leaves in whorls of 4-16, sometimes broader and with 3-5 palmate nerves; ripe mericarps ovoid to subglobose, with a longer zone of contact and with diverse surface structures; corolla diverse, but often rotate and always 4-merous		(8)
7 (6)	Inflorescences with many-flowered cymes; corolla 4-lobed, 2.5-4 mm in diam.; leaves mostly 15-20 × 5-8 mm.		27 G. karakulense
+	Inflorescences with 1-3(or 4)-flowered cymes; corolla mostly 3-lobed, 1-1.8 mm in diam.; leaves mostly 3-8 × 1-2 mm.		25 G. innocuum
8 (6)	Leaves and leaflike stipules in middle stem region never in whorls of more than 4 (if rarely in whorls of up to 6 then leaves with 3-5 palmate principal veins), from linear to broadly ovate		(9)
+	Leaves and leaflike stipules in middle stem region regularly in whorls of more than 4, i.e., in whorls of 5-16, with only 1 principal vein, linear to broadly lanceolate or elliptic, but never ovate or with a length/breadth index of less than 2.5		(44)
9 (9)	Stem apex vegetative, with few- to several-flowered lateral cymes only in leaf axils and shorter than or ± equal to subtending leaves, nodding in fruit.		Cruciata (see comments above)
+	Stem apex usually floriferous, with terminal and axillary cymes, often longer than subtending leaves and mostly not nodding in fruit		(10)
10 (9)	Condensed plants of rocks or high elevations; stems usually less than 10 cm tall, glabrous or with spreading (but never retrorse) hairs; leaves mostly ± ovate, (1-)3-8(-20) × (0.8-)2-4(-10) mm, with 1-3 main veins; corolla rotate, often only 1.5-2 mm in diam.; mericarps with spreading (rarely appressed) hooked or ± straight trichomes		(11)
+	Taller plants, usually of lower elevations with larger leaves (if plants ± condensed then stem hairs retrorsely curved or fruit hairs appressed but not hooked)		(18)
11 (10)	Mericarps with ± straight hairs, 2-2.5 mm in diam.; stems mostly pilose or hirtellous		(12)
+	Mericarps with weakly to strongly curved and uncinate trichomes; stems partly glabrous		(13)
12 (12)	Fruiting pedicels straight; Xizang.		47 G. serpylloides
+	Fruiting pedicels nodding; Taiwan.		36 G. nankotaizanum
13 (11)	Corolla ca. 3 mm in diam.; stems glabrous.		53 G. takasagomontanum
+	Corolla 1.2-2 mm in diam.; stems ± hairy or glabrous		(14)
14 (13)	Stems ± hairy		(15)
+	Stems glabrous; Taiwan		(16)
15 (14)	Leaves ovate to broadly lanceolate, acute, up to 3.5 mm wide; Yunnan.		44 G. rupifragum
+	Leaves broadly elliptic to obovate, obtuse and mucronate, up to 10 mm wide; Taiwan.		17 G. formosense
16 (14)	Leaves very small, only 0.8-1 mm wide, with 1 main vein only; fruit hairs spreading.		34 G. minutissimum
+	Leaves wider, with 1 or 3 main veins; fruit hairs appressed		(17)
17 (16)	Leaves with 3 main veins; corolla only ca. 1.2 mm in diam.		35 G. morii
+	Leaves with 1 main vein; corolla ca. 2 mm in diam.		54 G. tarokoense
18 (10)	Leaves with 1 principal vein or 2 lateral veins only weakly visible and not extending past middle of blade		(19)
+	Leaves with 3-5 palmate principal veins, lateral veins well marked and extending for more than half of blade length		(29)
19 (19)	Open corollas funnelform, 2.5-3 mm, tube somewhat shorter than lobes; fruit with pericarp smooth to granular, becoming slightly inflated, enclosing both mericarps at dispersal.		Microphysa elongata (see p. 216)
+	Open corollas rotate, fused basal part much shorter than lobes; mericarps clearly separated		(20)
20 (19)	Stems ± strigose-hirsute, with hairs ± retrorse (but not retrorsely aculeolate); leaves ovate or elliptic to linear-lanceolate, broadest ± in middle, at lower side usually with glandlike spots; flowers unisexual, usually yellowish, ± greenish, or reddish; fruit normally with uncinate trichomes		(21)
+	Stems glabrous or with indumentum, but not with retrorse hairs; leaves often broadest above middle and thinner, without glandlike spots; flowers usually bisexual		(23)
21 (20)	Plants usually less than 15 cm tall, strongly branched from base; leaves often less than 8 mm, mostly glabrescent or glabrous, subleathery; inflorescences with few-flowered, bracteate cymes.		20 G. glandulosum
+	Plants usually more than 15 cm tall, little branched; leaves usually longer than 8 mm, hairy on both sides; inflorescences paniculate to corymbiform, little bracteate		(22)
22 (21)	Leaves linear-elliptic to narrowly lanceolate, mostly 8-17 × 1-2.5 mm, dried rather papery; inflorescence paniculate.		21 G. hirtiflorum
+	Leaves ovate-elliptic, mostly 8-12 × 3-5 mm, dried rather subleathery; inflorescence corymbiform.		18 G. forrestii
23 (20)	Leaves ± linear, often longer than 20 mm, in addition to 1 principal, with 2 weaker lateral veins; corolla 4-5 mm in diam		(24)
+	Leaves not linear, mostly shorter than 20 mm; corolla smaller		(25)
24 (23)	Leaves linear-spatulate, 1-4 mm wide; inflorescences loose, broadly paniculiform; ovaries and fruit glabrous and smooth.		31 G. linearifolium
+	Leaves linear-lanceolate, 3-9 mm wide; inflorescences dense, elongate-paniculate; ovaries and fruit with sparse hooked trichomes or glabrous.		60 G. turkestanicum
25 (23)	Leaves ovate, length/breadth index 2 or less, in addition to 1 principal, with 2 weaker lateral veins; corolla larger; fruit with spreading hooked or straight hairs; Taiwan		(26)
+	Leaves ovate-oblong to lanceolate, length/breadth index 2 or more, with only 1 principal vein; corolla 1.5-2 mm in diam.; ovaries and fruit glabrous or with various indumentum		(27)
26 (25)	Mericarps with straight trichomes; corolla 2-2.5 mm in diam.; stems pilose or glabrescent.		36 G. nankotaizanum
+	Mericarps with hooked trichomes; corolla ca. 3 mm in diam.; stems glabrous.		53 G. takasagomontanum
27 (25)	Leaves dried subleathery; fruit with appressed, ± curved (but not uncinate) hairs; Shanxi.		12 G. crassifolium
+	Leaves dried papery; fruit with various indumentum		(28)
28 (27)	Plants ascending, weak, sparsely hairy or glabrous; inflorescence few flowered, peduncles and pedicels very thin and elongated, latter mostly 4-8 mm; fruit with spreading uncinate trichomes.		45 G. salwinense
+	Plant erect, more robust, indumentum diverse; inflorescences ± many flowered, peduncles and pedicels thicker and shorter, latter mostly 2-4 mm; fruit tuberculate, with appressed or spreading hooked trichomes, or more rarely smooth.		9 G. bungei
29 (18)	Corolla funnelform or cup-shaped, 2-5 mm in diam., with fused lower part ± as long as lobes; ovaries and fruit glabrous		(30)
+	Corolla rotate, (1-)2-5 mm in diam., with fused base much shorter than lobes		(32)
30 (29)	Corolla cup-shaped or campanulate, 2-2.7 mm in diam.; cauline leaves broadly lanceolate, always in whorls of 4.		30 G. kunmingense
+	Corolla funnelform or campanulate, 2.5-5 mm in diam.; middle stem leaves ovate to elliptic, in whorls of 4-6		(31)
31 (30)	Open corollas 3.5-5 mm in diam.; cauline leaves usually in whorls of 4, 12-28 mm.		40 G. platygalium
+	Open corollas 2.5-3.5 mm in diam.; cauline leaves in whorls of 4-6(-8), 23-53 mm.		32 G. maximoviczii
32 (29)	Leaves linear to linear-lanceolate, 27-40 × 3-9 mm, in addition to 1 principal, with 2 weaker lateral veins; corolla 4-5 mm in diam.; ovaries and fruit with sparse uncinate trichomes or glabrous.		60 G. turkestanicum
+	Leaves lanceolate to ovate, shorter, 3 principal veins mostly readily visible		(33)
33 (32)	Fruit glabrous, smooth to granular-papillose, or with appressed and ± hooked or with spreading and straight (but never with spreading and hooked) trichomes		(34)
+	Fruit with ± spreading and uncinate trichomes		(39)
34 (33)	Open corollas 3-4 mm in diam.; stems (except nodes) mostly glabrous and smooth		(35)
+	Open corollas (1-)2-2.5 mm in diam.; stems glabrous or ± hairy		(36)
35 (34)	Leaves ovate-lanceolate to ovate, papillose, length/breadth index mostly 2.5 or less; cymes rather few flowered; ovaries and fruit with ± appressed, apically somewhat bent trichomes.		10 G. chekiangense
+	Leaves mostly rather narrowly lanceolate, smooth or ± hairy, length/breadth index mostly 3 or more; cymes many flowered; ovaries and fruit glabrous or with various indumentum.		7 G. boreale
36 (34)	Cauline leaves broadly to narrowly lanceolate, length/breadth index often 3.5 or more		(37)
+	Cauline leaves narrowly to broadly ovate-lanceolate, length/breadth index usually 3 or less		(38)
37 (36)	Stems hairy throughout; leaves lanceolate; fruit with straight hairs or rarely glabrous.		24 G. hupehense
+	Stems (except nodes) glabrous; leaves ovate-lanceolate (sometimes also broader), apex subacute to acuminate, striate-punctate glandular below; fruit glabrous and smooth.		29 G. kinuta
38 (36)	Leaves 6-30 × 3-20 mm; fruiting pedicels straight; fruit glabrous or scaberulous; mainland.		15 G. elegans
+	Leaves 4-10 × 2-5 mm; fruiting pedicels nodding; fruit with ± straight trichomes; Taiwan.		36 G. nankotaizanum
39 (33)	Open corollas 3 mm or more in diam.; stems (except nodes) often glabrous and smooth		(40)
+	Open corollas 2.5 mm or less in diam.; stems often ± hairy		(42)
40 (39)	Leaves lanceolate to ovate-lanceolate or elliptic, length/breadth index 3.5 or more, apex acute to acuminate.		7 G. boreale
+	Leaves ovate, length/breadth index less than 3		(41)
41 (40)	Leaf apex obtuse to rounded, usually mucronate; mainland.		26 G. kamtschaticum
+	Leaf apex acuminate; Taiwan.		53 G. takasagomontanum
42 (39)	Leaves ovate-lanceolate to narrowly elliptic, with acute apex, length/breadth index normally more than 2.5.		63 G. yunnanense
+	Leaves ovate to broadly elliptic, with obtuse to rounded apex, entire or shortly mucronate, length/breadth index normally less than 2.5		(43)
43 (42)	Leaves up to 20 mm wide; plants slender to usually rather robust; mainland.		15 G. elegans
+	Leaves up to 10 mm wide; slender low plants; Taiwan.		17 G. formosense
44 (8)	Inflorescences capitate and enclosed by leaflike bracts; corolla funnelform or salverform, 4-15 mm, with 4 or 5 lobes		(45)
+	Inflorescences branched, not enclosed by bracts; corolla rotate, campanulate, or funnelform, 0.5-13 mm, mostly with 4 (rarely 3) lobes		(47)
45 (45)	Plants perennial, 20-70 cm tall; calyx limb obsolete; corolla 5-lobed, 12-14 mm.		Phuopsis stylosa (see p. 291)
+	Plants annual; corolla 4-lobed, shorter		(46)
46 (46)	Calyx teeth well developed; corolla pink, tube 4-5 mm.		Sherardia arvensis (see comments above)
+	Calyx lacking; corolla bluish, tube 7-13(-15) mm.		Asperula orientalis (see p. 78)
47 (44)	Medium stem leaves marginally (and often on upper side) with microhairs directed forward (use 20× lens), thus antrorsely ciliolate or aculeolate; stems mostly not retrorsely aculeolate		(48)
+	Medium stem leaves marginally (not on leaf surface) with microhairs directed backward (use 20× lens), thus retrorsely aculeolate or completely glabrous and smooth; stems often retrorsely aculeolate		(61)
48 (47)	Ovaries and fruit densely covered with uncinate trichomes; plants perennial with smooth stems		(49)
+	Ovaries and fruit glabrous or hairy, but never with uncinate trichomes; plants perennial or annual		(53)
49 (48)	Corolla funnelform, with tube ± as long as lobes.		37 G. odoratum
+	Corolla rotate, with tube markedly shorter than lobes		(50)
50 (49)	Robust, procumbent to ascending plants often longer than 50 cm; inflorescences terminal and lateral with cymes in upper 2-4 nodes.		59 G. triflorum
+	Slender erect plants, less than 50 cm tall; inflorescences predominantly terminal		(51)
51 (50)	Leaves 6-25 × 2-7 mm; open corollas ca. 2 mm in diam.; Taiwan (cf. also 53. G. takasagomontanum).		14 G. echinocarpum
+	Leaves often larger; open corollas 1.5-3.5 mm in diam.; mainland		(52)
52 (51)	Leaves mostly in whorls of 7 or 8, (ob)lanceolate, length/breadth index mostly 3.5-4.5, subpetiolate; fruit with uncinate trichomes 0.6-0.8 mm; expected in Xizang.		4 G. asperuloides
+	Leaves mostly in whorls of 6, narrowly obovate to broadly oblanceolate, length/breadth index mostly 2.5-3.5, clearly petiolate; fruit with uncinate trichomes 0.8-1.2 mm or longer; widespread.		22 G. hoffmeisteri
53 (48)	Plants annual, slender; flowers on pedicels and peduncles often longer than 5 mm and in lax, diffuse inflorescences		(54)
+	Plants perennial, slender to robust; flowers on pedicels and peduncles 0.5-5 mm, in lax to ± congested inflorescences		(56)
54 (54)	Leaves filiform, 20-30 mm, ascending; corolla funnelform, pink to red; ovary and mericarps with dense, short and curved hairs.		Leptunis trichodes (see p. 213)
+	Leaves linear to oblanceolate, 4-20 mm, spreading to reflexed; corolla ± rotate, whitish, yellowish, or greenish; ovary and fruit glabrous or slightly tuberculate		(55)
55 (54)	Inflorescences broadly ovate, diffuse and intricate, with fruiting pedicels elongated to 20 mm.		55 G. tenuissimum
+	Inflorescences rather narrowly thyrsoid, not diffuse and intricate, with fruiting pedicels only up to 4 mm.		19 G. ghilanicum
56 (53)	Corolla funnelform, lobed for 1/2-2/3, white		(57)
+	Corolla rotate, lobed for 3/4 or more, often yellowish; plants erect to ascending		(58)
57 (56)	Inflorescences lax, ± ebracteate; stems erect, smooth; main stem leaves 15-65 × 3-12 mm.		38 G. paniculatum
+	Inflorescences congested, strongly bracteate; stems procumbent, mostly ± hairy; main stem leaves 5-23 × 1-2(-5) mm.		23 G. humifusum
58 (56)	Leaves in middle stem region in whorls of not more than 6; plants of (sub)alpine region, not taller than 30 cm.		46 G. saurense
+	Leaves in middle stem region in whorls of more than 6 and up to 12		(59)
59 (58)	Open corollas 3.5-5 mm in diam., white; fruit somewhat spongy or fleshy, 3-3.5 mm, with a dry pericarp separating from rest of fruit.		8 G. bullatum
+	Open corollas ca. 3 mm in diam., yellow to whitish; fruit with dry mericarps, 1.5-2 mm, with pericarp dark and firmly attached to rest of fruit		(60)
60 (59)	Leaves mostly 2.5-5 mm wide, glabrous abaxially; fruit ca. 1.5 mm.		11 G. consanguineum
+	Leaves 1-2.5 mm wide, glabrous to densely pubescent abaxially; fruit 1.5-2 mm.		62 G. verum
61 (47)	Annuals, often in ± disturbed, weedy habitats; stems and leaf margins retrorsely aculeolate; fully developed mericarps subspherical, 2-6 mm; open corollas 1-2 mm in diam		(62)
+	Perennials, in ± natural habitats; fully developed mericarps ellipsoid, 1.5-3 mm; open corollas 1-4 mm in diam		(64)
62 (61)	Fruit becoming pendulous on arching peduncles and pedicels, verrucose to spinulose; leaves glabrescent above.		57 G. tricornutum
+	Fruit on divaricate straight peduncles and pedicels (only latter sometimes bent just beneath fruit), mostly with uncinate trichomes; leaves ± hairy above		(63)
63 (62)	Open corollas 1.5-2 mm in diam.; individual mature mericarps 2.5-5 mm in diam., with trichomes arising from tuberculate bases.		2 G. aparine
+	Open corollas 1-1.5 mm in diam.; individual mature mericarps 1-3 mm in diam., with trichomes straight from base.		50 G. spurium
64 (61)	Middle stem leaves narrowly obovate to oblanceolate, mostly 18-28 × 5-10 mm; stems slightly retrorsely aculeolate; inflorescences of medium size, with terminal and lateral, few- to several-flowered, rather loose cymes with small bracts, in fruit stiffly divaricate; corolla rotate, 1.5-2 mm in diam.; fruit with hooked trichomes.		58 G. trifloriforme
+	Middle stem leaves mostly smaller; inflorescences different, usually more bracteate; fruit smooth, verrucose, or with hooked trichomes		(65)
65 (64)	Corolla funnelform to subcampanulate, with tube ± as long as or slightly shorter than lobes, whitish; ovaries and fruit glabrous, smooth or verrucose; leaves papery to subleathery and glossy; stems rough, retrorsely aculeolate, procumbent to clambering		(66)
+	Corolla rotate, fused basal part much shorter than lobes; ovaries and fruit with hooked trichomes, tuberculate, or glabrous; stems glabrous, rough, or hairy		(67)
66 (65)	Corolla funnelform; plants robust, 0.6-1.2 m, often forming mats; main stem leaves 8-50 × 2-8 mm.		28 G. karataviense
+	Corolla subcampanulate; plants slender and ± erect, 10-60 cm tall; main stem leaves 3-16 × 1-3 mm.		61 G. uliginosum
67 (65)	Middle stem leaves larger, (5-)10-35(-50) × (1-)2.5-10 mm, mostly ± hairy, at least margins retrorsely aculeolate; cymes lateral and terminal, many flowered; ovaries and fruit glabrous or with diverse indumentum; plants from lower elevations, relatively robust, erect or clambering, stems up to 0.7 m tall		(68)
+	Middle stem leaves uniformly small, 2-12(-15) × 0.3-3.5 mm, glabrous and smooth to ± hairy; cymes lateral and terminal, few flowered; ovaries and fruit with uncinate (very rarely ± straight) trichomes or glabrous; plants from high elevations, usually reduced and weak, caespitose to procumbent, stems only up to 0.3 m		(74)
68 (67)	Stems branched from base; cymes leafy, with bracts to last branches; stems and leaves (nodes and margins excepted) glabrous and smooth; mericarps with spreading uncinate trichomes.		48 G. sichuanense
+	Stems normally branched from middle; cymes usually less leafy; stems and leaves mostly with more indumentum; fruit glabrous, papillose, tuberculate, or with uncinate trichomes		(69)
69 (68)	Peduncles and pedicels slender, filiform and often ± flexuose, with inconspicuous bracts; pedicels up to 5 mm, in fruit elongated to 10 mm or more; flowers never reddish; plants usually clambering; ovary and fruit surfaces diverse		(70)
+	Peduncles and pedicels rather stiff and often divaricate and ± bracteate; pedicels shorter than 5 mm and hardly elongated in fruit; ovary and fruit surfaces diverse, but often glabrous		(71)
70 (69)	Fruit often with uncinate trichomes; mainland.		13 G. dahuricum
+	Fruit glabrous; Taiwan.		52 G. taiwanense
71 (69)	Corolla red to purple (very rarely maroon or white), 1.5-2.5 mm in diam		6 G. blinii
+	Corolla whitish, yellowish, or greenish		(72)
72 (71)	Corolla small, 1.5-2 mm in diam., yellow to greenish white, lobes aristate; inflorescences divaricate and regularly bracteate with bracts similar to but smaller than leaves, giving a diffuse miniature aspect; ovary and fruit surface variable; plants often clambering.		3 G. asperifolium
+	Corolla larger, mostly more than 2 mm in diam.; inflorescences ebracteate or with bracts ± reduced and irregularly distributed; ovary and fruit surface smooth to tuberculate; plants erect, hardly clambering		(73)
73 (72)	Leaves lanceolate, gradually narrowed into acute apex.		41 G. prattii
+	Leaves subspatulate to obovate, apex rounded and abruptly narrowed into a mucro.		56 G. tokyoense
74 (67)	Ovaries and fruit with uncinate (very rarely ± straight) trichomes		(75)
+	Ovaries and fruit glabrous, smooth, papillose, or verrucose; Himalaya		(78)
75 (74)	Leaves and stems ± densely hispid and often retrorsely aculeolate; stems with 4 conspicuous whitish angles.		42 G. pusillosetosum
+	Leaves completely glabrous and smooth or only slightly hairy and/or retrorsely aculeolate; stems with 4 inconspicuous angles		(76)
76 (75)	Leaves dried blackening, papery and thin, oblanceolate to narrowly obovate, with flat margins, hardly longer than 7 mm.		5 G. baldensiforme
+	Leaves dried greenish-brownish, with ± revolute margins, often longer than 7 mm		(77)
77 (76)	Plants nearly always smooth; leaves ± subleathery; ovary in flower ca. 1 mm.		49 G. glabriusculum
+	Plants retrorsely aculeolate at least on margins and lower side of papery leaves; ovary in flower 0.5-0.8 mm.		51 G. sungpanense
78 (74)	Plants weak to procumbent but not mat-forming; cells of adaxial leaf surface relatively large, readily visible individually with 20× lens; corolla mostly whitish.		33 G. megacyttarion
+	Plants procumbent and often mat-forming; cells of adaxial leaf surface small, not or hardly visible individually with 20× lens		(79)
79 (78)	Stems ± densely hairy and/or retrorsely aculeolate, with 4 conspicuous whitish angles.		42 G. pusillosetosum
+	Stems glabrous or only slightly retrorsely aculeolate, with inconspicuous angles		(80)
80 (79)	Leaves on main stems 2-8.5 mm; inflorescence cymes 1- to few flowered, fascicled; corolla white, pale green, or pale yellow, with upper surface of lobes papillose.		1 G. acutum
+	Leaves on main stems 5-10.5 mm; inflorescence cymes 1-6-flowered; corolla nearly always red or purple, with upper surface of lobes glabrous and smooth except ± puberulent on margins and central vein.		43 G. rebae