Creeping cinderella-weed

Calyptocarpus vialis, the creeping cinderella-weed or horseherb, is a low-growing perennial herb of the daisy family (Asteraceae) that forms wide mats by means of decumbent, often rooting stems. The opposite leaves are simple, triangular to lanceolate, 1–3 cm long, with bluntly toothed margins and a rough texture from short stiff hairs on both surfaces. Small yellow flowerheads 2–5 mm long are borne almost year-round on short axillary peduncles, each containing around 10–20 disc florets and 3–8 short ray florets, and producing small, two-awned achenes adapted for animal dispersal. It is native to southern Texas, Mexico, Belize, Venezuela and parts of the Caribbean, and has been widely introduced east of Texas in the southern United States, as well as to Argentina, Hawai‘i, India, Java, Taiwan and Australia, where it persists as a weed of lawns, paths and disturbed ground.