Emex spinosa
(L.) Campd. Lesser JackLike Emex australis but plants usually erect, to c. 60 cm high, and leaves often larger, to 12 cm long, 8 cm wide. Fruiting perianth 5–7 mm long, 3–4 mm wide in the lower part, the sides each with a central rib bordered by 2–4 pits on either side, and a horizontal ridge at the widest point, shortly above the base, spines thick, spreading (or slightly recurved) to c. 6 mm diam., inner segments c. 1 mm wide at apex of tube, more or less oblong with a longitudinal, sometimes tuberculate ridge, acute at apex, not reticulate. Nut as for E. australis. Flowers Sep. (1 record).
MuM, GipP. Also naturalised WA, SA. Native to the Mediterranean region. Recorded in Victoria only twice, beside an irrigation channel at Merbein (1979), and in a degraded, previously cropped paddock at Neds Corner Station (2011).
Possibly occasionally hybridizes with Emex australis, specimens of intermediate fruit characters have been noted in South Australia.
Walsh, N.G. (1996). Polygonaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 3, Dicotyledons Winteraceae to Myrtaceae, pp. 272–295. Inkata Press, Melbourne.