Annual with decumbent to ascending, glabrous stems, 12-30 cm, branching from the base. Leaves in false whorls at the nodes, 10-25 mm, linear-subulate, glabrous, axillary sterile shoots often present. Flowers solitary or in few-flowered cymes. Pedicels slender, much longer than the calyx. Sepals 3-4.5 mm, ovate-lanceolate, glabrous, with white scarious margins. Petals white, lanceolate, entire, Shorter than the sepals. Seeds 1-1.5 mm, globose, black-brown, smooth, with shiny white membranous wing, almost as broad as the seed body.

Fl. Per.: March-June.

Type: Described from Madeira.

Distribution: S. W. Asia & Central India, N. Africa, Madiera, Canary Islands; B-7 Mardan Dist.: Rustam, M. A. Kazmi 1115 (RAW); C-6 Peshawar, 15.4.1956, Sadiq Masih s.n. (KUH); Islamia College area, A. R. Beg 118 (PPFI-B); Forest College, M. A. Ali 19 (PPFI-B); Burj Hari Singh, S. B. Akhtar 8 (PPFI-B); Peshawar, M. Nath 15403 (RAW); id., Yar Hussain & Farrakh Hussain 6737 (RAW); Warsak, Y, Mohd 11 (PPFI-B); C-7 Rawalpindi Dist.: Saidpur, in fields, Sham Mohan Lal 8 (RAW); Topi Park, Dwarka Nath 377 (RAW); Gujar Khan, 8.4.51, M. Y. Kiani (RAW); Rawalpindi, A. Jalis 1275 (RAW); Rawalpindi Agri. Farm, Y. Nasir 3335 (RAW); D-4 Mianwali Dist.: Dadu Khel, R. R. Stewart 26909 (RAW); D-7 Faisalabad Dist.: Lyallpur, A. Jalis 1311 (RAW); Baluchistan: G-2 S. Makran, 5½ miles from Mund, S. I. Ali, S. A. Farooqi & Sultan-ul-Abedin 1021 (KUH); Sind: G-4 Chuhar, off Malir Cantt., S. M. A. Jafri 1311 (KUH, E); G-5 Darshano Chino, white, Sultan-ul-Abedin 1355 (KUH).

Very similar to S. arvensis and difficult to tell apart. The main difference is in the presence of broadly winged seeds in S. fallax than in S. arvensis. Found in waste places in fields.