Calyptocarpus vialis is a species of flowering plant in the daisy family, Asteraceae. Common names for C. vialis include straggler daisy, horseherb, lawnflower, and creeping Cinderella-weed.It is native to the southern United States, Mexico, Belize, Venezuela, and the Caribbean. It has also been introduced to Argentina, Hawaii, India, Java, Australia, and Taiwan. It is one of only three species in the genus Calyptocarpus.The opposite leaves are typically 1–3 cm (0.39–1.18 in) long and triangular to lanceolate in shape. It bears heads of yellow flowers, with around 10–20 disc florets and 3–8 ray florets, the laminae of the latter around 2–5 mm (0.079–0.197 in) long. It flowers year round. It is a weedy species, found in lawns and along other disturbed areas such as roadsides and paths.
Invasive in eastern Asia and Africa and in India.