Citation: L., Sp. Pl. 2:987 (1753).

Synonymy: Not Applicable

Common name: None

Description:
Annual herbs; leaves cauline, alternate, petiolate, flat, simple, variously lobed or dentate.

Capitula unisexual, monoecious, sessile in terminal and axillary clusters, male above, female below; male capitula globose; involucral bracts few, narrow, smooth, in 1 or 2 series; receptacle hemispherical, with scales; florets numerous, tubular, pentamerous; anthers obtuse at the base, with a short appendage at the apex; ovary and style abortive; female capitula ovoid; involucral bracts 2-seriate, the outer few free, the inner 2 connate and completely enclosing the florets, spiny, 2-beaked at the apex; florets 2; corolla absent; style branches flliform, exserted from the base of the beaks of the involucre.

Achenes retained inside the involucre which enlarges and is shed as a unit; pappus absent. (C. McMillan (1975) Aust. J. Bot. 23:173-192).

Distribution:  About 30 species widespread in temperate and tropical regions, about 5 naturalised in Australia.

Biology: No text

Key to Species:

1. Leaves dark-green above, whitish below; stems bearing 3-fid spines below each leaf	X. spinosum 3.
1. Leaves green on both surfaces; stems lacking spines
2. Fruiting capitulum with spines 3-5 mm long; beaks diverging and incurved	X. californicum 1.
2. Fruiting capitulum with spines 2-3 mm long; beaks approximate and almost straight	X. occidentale 2.

Author: Not yet available