1. Cynodon radiatus Roth ex Roemer & Schultes, Syst. Veg. 2: 411. 1817.
弯穗狗牙根 wan sui gou ya gen
Cynodon arcuatus J. Presl in C. Presl; C. dactylon var. in-termedius (Rangachari & Tadulingham) C. E. C. Fischer; C. in-termedius Rangachari & Tadulingham.
Perennial, stoloniferous, widely spreading, without rhizomes. Culms slender, 20–50(–80) cm tall. Leaf sheaths glabrous or pilose at mouth; leaf blades broadly linear, 2.5–10(–15) cm, 3–6 mm wide, glaucous, glabrous, apex acute; ligule ca. 3 mm, membranous, ciliolate on upper edge. Racemes digitate, usually 4–8, 5–10 cm, flexuous, slightly drooping; spikelets overlapping by 1/3–1/2 their length. Spikelets 1.8–2.5 mm; rachilla extension ca. 1 mm, without reduced floret at apex; glumes lanceolate, about half as long as floret, 1-veined, keel scabrous, thickened; lower glume ca. 1 mm; upper glume 1–1.4 mm; lemma as long as spikelet, pilose along keel and lateral veins, hairs sometimes clavate, apex subacute; palea glabrous, keels smooth or rarely scaberulous. Anthers 0.5–0.7 mm. Caryopsis trigonous, laterally compressed. Fl. and fr. Jul–Nov. 2n = 36.
Sunny open places, roadsides. Guangdong (offshore islands), Hainan, Taiwan [Bhutan, India, Indonesia, Malaysia, Myanmar, Nepal, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; N Australia; Madagascar].
The club-shaped tips to the lemma hairs can be seen only under a microscope. This species is easily confused with Cynodon dactylon, from which it differs mainly in the absence of rhizomes. It is genetically isolated from all other species of Cynodon.