Plants annual, ± delicate, 6-25+ cm, often densely stipitate-glandular, at least in inflorescence. Taproots ± filiform. Stems erect to spreading or sprawling, usually much-branched proximally; main stem 0.5-1 mm diam. proximally. Leaves: stipules usually inconspicuous, dull white to tan, broadly triangular, 1.5-4.5 mm, apex acute to short-acuminate; blade ± linear, 1-4.2 cm, at least moderately fleshy, apex apiculate to spine-tipped; axillary leaves absent or 1-2 per cluster. Cymes simple to 6+-compound. Pedicels often oriented to 1 side in fruit. Flowers: sepals connate 0.3-0.6 mm proximally, lobes often 3-veined, ovate to elliptic-oblong, 2.2-3.5 mm, to 4.5 mm in fruit, margins 0.2-0.5 mm wide, apex acute to rounded; petals white or pink to rosy, ovate to obovate, 0.8-1 times as long as sepals; stamens 8-10; styles 0.4-0.6 mm. Capsules greenish, 3(-4) mm, 1-1.2 times as long as sepals. Seeds light brown, with submarginal groove, broadly ovate, plump, 0.4-0.6 mm, somewhat shiny, smooth to minutely roughened, margins with peglike papillae (40×); wing absent. 2n = 18- (Africa), 36 (Europe).
Flowering spring. Salt marshes, alkaline places, sandy soils; 0-400 m; introduced; Calif., Oreg.; sw Europe (Mediterranean region).
The spelling of the epithet bocconi, often 'corrected' to bocconii, is debatable. It commemorates Paolo Boccone, suggesting a correction to bocconei, but he also used the Latinized form Bocconus, allowing bocconi. We have used bocconi, following the first usage by Scheele.