50. Galium spurium Linnaeus, Sp. Pl. 1: 106. 1753.
猪殃殃 zhu yang yang
Galium agreste Wallroth; G. agreste var. echinospermum Wallroth; G. agreste var. leiospermum Wallroth; G. aparine Linnaeus var. echinospermum (Wallroth) T. Durand; G. aparine f. leiocarpum Makino; G. aparine var. leiospermum (Wallroth) T. Durand; G. aparine var. spurium (Linnaeus) W. D. J. Koch; G. aparine var. tenerum (Grenier & Godron) H. G. Reichenbach; G. aparine var. vaillantii (Candolle) W. D. J. Koch; G. hongnoense H. Léveillé; G. oliganthum Nakai & Kitagawa; G. pauciflorum Bunge (1833), not Willdenow ex Candolle (1830); G. spurium var. echinospermum (Wallroth) Hayek; G. spurium var. tenerum Grenier & Godron; G. vaillantii Candolle; G. wutaicum Hurusawa.
Herbs, annual, procumbent or climbing, 30-50 cm tall. Stems 4-angled, 0.5-2.5 mm in diam., ± branched from base, retrorsely aculeate on angles, glabrescent to pilose at nodes. Leaves at middle stem region in whorls of 6-8, subsessile; blade drying papery, narrowly oblanceolate to narrowly oblong-oblanceolate, 5-40 × 1-5(-8) mm, usually pilosulous or hispidulous adaxially, retrorsely aculeolate along midrib abaxially and along margins, base acute, margins flat to thinly revolute, apex acute and shortly mucronate; vein 1. Inflorescences terminal and axillary, cymes 2- to several flowered; axes glabrous to aculeolate; bracts leaflike or none, 1-5 mm; peduncles 1-4 cm; pedicels 0.5-15 mm, finally elongating and often curved directly under fruit. Ovary subglobose, 0.3-0.5 mm, with uncinate trichomes or glabrous. Corolla yellowish green or white, rotate, 1-1.5 mm in diam., lobed for 2/3 or more; lobes 4, triangular to ovate, acute. Mericarps subglobose to broadly kidney-shaped, 1-3 mm in diam., glabrous or often densely covered with uncinate trichomes 0.1-1 mm from straight bases. Fl. Mar-Jul, fr. Apr-Nov.
Open fields, riversides, farmlands, mountain slopes; near sea level to 4600 m. Common and widespread throughout China except Hainan and Nanhai Zhudao [Africa, Eurasia, and the Mediterranean; today sporadically adventive worldwide].
This species is occasionally used medicinally.
Galium spurium consists of basal elements (2x and 4x, 2n = 20, 40) of a polymorphic polyploid complex, the G. aparine group or G. aparine s.l. (see there). Following Ehrendorfer et al. (Fl. Iranica 176: 234. 2005), G. spurium is maintained here at the species level, with particular reference to its differential characters in flower and fruit size, and not included under the higher polyploid and aneuploid G. aparine s.s., as in Cufodontis (Oesterr. Bot. Z. 89: 245-247. 1940) and W. C. Chen (in FRPS 71(2): 237. 1999). Galium spurium is very common and widespread in China, in contrast to the rare and partly doubtful G. aparine s.s. To our knowledge, no chromosome counts are yet available from Chinese populations of G. spurium. Nevertheless, a report of 2n = 40 for this species from Novosibirsk (Krasnikov & Schaulo, Bot. Žurn. 75: 118-120. 1990) suggests the occurrence of 4x G. spurium cytotypes in Asia, corresponding to similar 4x-cytotypes reported from Africa.
From the varieties recognized by Cufodontis (loc. cit.) and accepted by W. C. Chen (loc. cit.: 234-237) Galium spurium var. tenerum refers to reduced specimens, which can appear under extreme conditions as modifications everywhere, and are taxonomically irrelevant. But as genetically fixed reduced alpine ecotypes they deserve a name: G. spurium subsp. ibicinum (Boissier & Haussknecht) Ehrendorfer, described from high mountains in SW Asia (see Ehrendorfer et al., loc. cit.: 236). Some condensed alpine Chinese specimens may belong to this taxon.
In contrast, Galium spurium var. echinospermum vs. var. spurium (= G. aparine var. leiospermum) refer to genetically fixed forms with uncinate hairy vs. glabrous fruit, which in W Eurasia and the Mediterranean often occur together in the same population and can be separated as taxonomic forms. In China we have seen only the echinospermum type, whereas var. spurium apparently is missing there. The reference to it by W. C. Chen (loc. cit.: 237) concerns the glabrous fruited G. ghilanicum (see there). It is obvious that a more detailed analysis of the G. aparine-G. spurium polyploid complex in E Asia is badly needed.
The enormous variability of Galium aparine and G. spurium has caused its many synonyms and common misidentifications with other annual and even perennial taxa of Galium. This applies in particular to the annual G. tricornutum, which differs by strongly verrucose (but not uncinate hairy) fruit, and to the perennial taxa with retrorsely aculeolate stems and fruit with uncinate hairs, such as G. sungpanense (see there), G. dahuricum, etc., which often have larger flowers.