Habit: annual to short-lived perennial herb (to 30 cm).
Habitat: between marl, and in the crevices of masonry.
Distribution: Native to tropical South America. Naturalized from southern China (and in greenhouses in northern China), and south throughout South-East Asia.
Collections: Timor Barat: Nikiniki, Kooy 17, 4 Feb 1965 (L); Lahurus, Schmutz 2231, 20 Jun 1968 (L); Timor-Leste: Ossu-Viqueque road, in Loihuno, near Viqueque, Paiva, Silveira & Sousa T496, 15 Feb 2005 (AVE, L); Viqueque-Baucau road, before Mount Laritame, Paiva, Silveira & Sousa T585, 17 Feb 2005 (AVE, L).