Trianthema portulacastrum (Flora of the WAP complex - non-leguminous dicots)

Trianthema portulacastrum

Summary ⁴

Trianthema portulacastrum is a species of flowering plant in the ice plant family known by the common names desert horse purslane, black pigweed, and giant pigweed. It is native to areas of several continents, including Africa and North and South America, and present as an introduced species in many other areas. It grows in a wide variety of habitat types and it can easily take hold in disturbed areas and cultivated land as a weed. It...

Description ⁵

Prostrate annual herb, somewhat succulennt, with spreading stems up to 50 cm long, mostly hairless except for very young parts. Leaves opposite, usually one in each pair smaller than the other, more or less broadly obovate to almost circular, 3-45 mm long, hairless or sparsely hairy on the midrib beneath; margin entire; petiole up to 20 mm long, expanding at the base into a sheathing membrane connecting with the base of the opposite leaf. Stipules up to 3 mm long. Flowers solitary in the leaf axils, often partly hidden by the sheathing leaf-bases.Perianth segments up to 5 mm long, pinkish or yellowish; stamens 10-20.

Diagnostic ⁶

"Prostrate or ascending succulent herbs; branchlets pubescent on one side, thickened at the nodes. Leaves opposite or subopposite, unequal, 1.2-3.5 x 0.8-2.2 cm, orbicular-obovate, oblong or elliptic, base obtuse or attenuate, margins entire, often undulate, purplish, apex obtuse, rounded or retuse, sub-succulent; petiole sheathing with two stipule-like appendages. Flowers c. 7 mm across, axillary, solitary, sessile, sheathed by the base of the petiole. Calyx tube c. 1.5 mm long, adnate to base of petiole; lobes 5, white or pink, c. 4 mm long, oblong, obtuse. Stamens 15-20. Capsule to 5 mm long, turbinate, apex truncate, 2-lobed, brown, circumscissile. Seeds black with muricate concentric lines."

Sources and Credits

(c) Alexis López Hernández, some rights reserved (CC BY), uploaded by Alexis López Hernández
(c) 2014 Richard Spellenberg, some rights reserved (CC BY-NC-SA), http://calphotos.berkeley.edu/cgi/img_query?seq_num=614854&one=T
(c) 2014 Richard Spellenberg, some rights reserved (CC BY-NC-SA), http://calphotos.berkeley.edu/cgi/img_query?seq_num=614855&one=T
(c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Trianthema_portulacastrum
(c) Mark Hyde, Bart Wursten and Petra Ballings, some rights reserved (CC BY-NC), http://eol.org/data_objects/30291749
(c) India Biodiversity Portal, some rights reserved (CC BY), http://eol.org/data_objects/26334960