3. Galium asperifolium Wallich in Roxburgh, Fl. Ind. 1: 381. 1820.
楔叶律 xie ye lü
?Galium cavaleriei H. Léveillé; ?G. esquirolii H. Léveillé.
Herbs, perennial, weak to climbing or trailing, usually much branched. Stems 20-70 cm, 4-angled to 4-winged, villosulous to hirtellous and/or sparsely aculeolate to smooth. Leaves on main stems in whorls of up to 6(-8), sessile or with very short (ca. 1 mm) petiole; blade drying papery to leathery, adaxially dark green and shiny, abaxially paler, oblanceolate-oblong, oblanceolate, or obovate, (5-)10-20(-25) × (1-)1.5-4(-6) mm, adaxially scaberulous, hirtellous to glabrous, abaxially densely villosulous, hirsute, pilose to glabrous, base acute to cuneate, margins retrorsely aculeolate and ± hairy, flat to thinly revolute, apex obtuse, rounded, truncate, or emarginate and shortly mucronate; vein 1. Inflorescences ± paniculate, up to 18 cm, expanding through growing season, with terminal and axillary, several- to many-flowered cymes; peduncles glabrous to rarely villosulous, regularly spreading to divaricate, with a dichasial branching pattern, at most nodes with leaflike bracts (1-4 mm); pedicels 0.2-2.5 mm. Ovary obovoid, 0.2-0.3 mm, mostly glabrous or smooth, but sometimes also verrucose, hirtellous, or with undeveloped uncinate trichomes. Corolla greenish white or yellow, rotate, 1.5-2 mm in diam., glabrous, lobed for 2/3 or more; lobes 4, triangular-ovate, filamentous-aristate (rarely only acute). Mericarps ellipsoid, 1-2 mm, glabrous and smooth or rarely granular-tuberculate, hirtellous, or with appressed to spreading hooked trichomes, on pedicels often slightly elongating to 4 mm. Fl. and fr. (May-)Jun-Sep(-Oct).
Mountain slopes, farmland sides, riversides and beaches, grasslands, forests, thickets, ditch sides, open fields, meadows; 400-3500 m. Guangxi, Guizhou, Hubei, Hunan, Sichuan, Xizang, Yunnan [Afghanistan, Bangladesh, Bhutan, India, Nepal, Pakistan, Sri Lanka, Thailand].
Galium asperifolium is an exceedingly variable and widespread species and was the first described from a larger assembly of taxa, here called G. asperifolium group and provisionally placed into G. sect. Trachygalium (but certainly not into G. sect. Leptogalium as in Yamazaki, Fl. Japan 3a: 238-239. 1993, or into G. sect. Leiogalium as in W. C. Chen, FRPS 71(2): 271. 1999). According to Cufodontis (Oesterr. Bot. Z. 211-251. 1940), Nazimuddin and Ehrendorfer (Pl. Syst. Evol. 155: 71-75. 1987), Mill (Edinburgh J. Bot. 53: 193-213. 1996; Fl. Bhutan 2(2): 825-834. 1999), Ehrendorfer et al. (Fl. Iranica 176: 194. 2005), and the present treatment, the center of diversity of the G. asperifolium group lies in the E Himalaya and SW China. Within this area, two subgroups of taxa can be recognized, one with larger plants, longer than 10 mm middle stem leaves, and many-flowered cymes from lower eleva- tions (1), the other with more condensed growth, shorter middle stem leaves, and 1- to few-flowered cymes from higher elevations (2). Both subgroups include taxa with whitish, yellowish to greenish, and others with reddish, purplish, or brownish flower color. The (sub)alpine subgroup (2) is briefly surveyed under G. acutum. Subgroup (1), discussed here, is represented by taxa with ± whitish flowers: G. subfalcatum Nazimuddin & Ehrendorfer and G. campylotrichum Nazimuddin & Ehrendorfer in the W Himalaya of Pakistan and the widespread G. asperifolium with its var. sikkimense (= G. sikkimense) in the C and E Himalaya (including Bhutan). In addition, subgroup (1) includes taxa with a more easterly distribution, extending from China into the remaining parts of E Asia (including Japan): G. dahuricum (including G. comarii, G. manshuricum, G. niewerthii, and G. pseudoasprellum), G. prattii, G. taiwanense, and G. tokyoense. Subgroup (1) taxa with reddish flowers are G. blinii in SW China and the newly described Bhutan endemic G. craticulatum R. R. Mill (see also Mill, loc. cit. 1996; loc. cit. 1999).
Because of its great variability with respect to habit and the indumentum of stems, leaves, and fruit, Galium asperifolium is often not easily separable from its closest relatives, and transitional forms occur. Its best differential characters are the many-flowered, divaricate, distally dichasial branching, and strongly bracteate cymes and the small yellowish-greenish flowers with aristate corolla lobes. Galium blinii mainly deviates by larger, reddish flowers and non-aristate corolla lobes. The filiform and flexuose peduncles and pedicels separate G. dahuricum, and the less bracteate inflorescences and larger flowers separate G. prattii, G. taiwanense, and G. tokyoense. To the taxa of the (sub)alpine subgroup (2, e.g., G. acutum) G. asperifolium is linked particularly through its var. sikkimense.
In addition to its natural complexity, the taxonomy of the Galium asperifolium group is rendered difficult by a number of badly described and insufficiently documented species created by H. Léveillé. On the basis of the studies by Cufodontis (loc. cit.), Lauener and Ferguson (Notes Roy. Bot. Gard. Edinburgh 32: 103-115. 1973), Mill (loc. cit. 1996), and our own judgment, we suggest to dispose of them in the following way: Galium blinii is maintained as a separate species (possibly with G. bodinieri and G. quinatum as synonyms), whereas G. cavaleriei and G. esquirolii (and "G. cuneatum H. Léveillé," though a nomen nudum) are provisionally assigned as synonyms to G. asperifolium s.l. (including var. sikkimense); G. comarii and G. niewerthii are treated as synonyms of G. dahuricum.
The following schematic key to the varieties of Galium asperifolium corresponds to W. C. Chen (loc. cit.: 271-274) who mainly followed Cufodontis (loc. cit.: 239-240). Only G. asperifolium var. setosum has been eliminated because it clearly is a synonym of G. acutum. Individuals with uncinate trichomes on ovaries and fruit, but otherwise identical to typical G. asperifolium, are reported here for the first time. They still lack a varietal name and are provisionally accommodated under var. asperifolium. In contrast to Mill (loc. cit. 1996; loc. cit. 1999), G. sikkimense is here again reduced to varietal status under G. asperifolium, following Cufodontis (loc. cit.: 241). Forms of this species with ± glabrescent stems dominate to the east of its wide distribution area, but intraspecific and local variation of stem indumentum is so extensive and continuous as to make this character useless as a basis for specific separation. Mill (loc. cit. 1996: 201-212) assumed G. asperifolium var. asperifolium to be most common in C and W Nepal and to be replaced by var. sikkimense toward the east. This statement is in conflict with the data on distribution in China from Chen (loc. cit.) and our own observations presented below. In view of the taxonomical complexity of the G. asperifolium group and the common misinterpretation of its members, further careful studies are obligatory.