Vulgar names: "yerba meona", "yerba of paloma", "yerba of golondrina", "lechetres", "lechera"; "caá-cambuy", "caá-ambuí", "tupaci-cambuy", "tupa-sig-cambú", "aaré", "kapindéi" in language tufa; "willéñ kachú" (grass of piss) in araucano-Pampas.
Geographic distribution and habitat: From the United States (Georgia) Center America, Panama to Argentina. It is very common on the foot of walls, gardens, orchards, edges of sidewalks.
Brief description of the plant: Grass postroad, perennial, with alternate ramifications and naked radicantes, glabras. Opposed, ovado-circular leaves to oblong, of whole edges, unequally cordadas in the base, short pecioladas. The smallest, terminal flowers. Fruit, ovoid, smaller capsule of 2mm., with ovoid and smooth seeds. It blooms in summer.
Uses and used part: The whole plant is used like diurético and emenagogo; látex is antitumorlike, drastic, against diseases of the skin (calluses, warts, herpes, tattoos, of external use).
Often replaced by red Spergularia (L.) J. ET C. Presl., according to Amorín (1969).
Obs.: According to Amorín (1977:18) it happens the inverse case frequently: to replace "arenaria red Spergularia roja", by Euphorbia serpens "meona".