海滨大戟 hai bin da ji

Chamaesyce atoto (G. Forster) Croizat; Euphorbia articulata Dennstedt (1818), not Burman (1760); E. atoto var. minor Boissier; E. halophila Miquel; E. pallens Dillwyn; E. lingiana Shih ex Chun.

Herbs, perennial, 20-40(-60) cm tall. Rootstock woody, 8-10 mm thick. Stems woody at base, many branched, each branched again, ascending or suberect, to 8-10 mm thick at base; internodes large and conspicuous. Leaves opposite, mostly not overlapping; stipules mostly interpetiolar, membranous, triangular, 1-2 mm, lacerate, caducous when dry; petiole 1-3 mm; leaf blade long elliptic or ovate-oblong, 1-3(-4) × 0.4-1.3(-1.5) cm, thinly leathery, base obliquely subrounded or rounded-cordate, margin entire, apex a small tip, obtuse in upper; lateral veins pinnate. Cyathia in terminal and subterminal cymes, peduncle 2-5 mm; involucre cuplike, ca. 2 × 1.5 mm, marginal lobes (4 or)5, triangular-ovate, apex acute, lacerate; glands 4, yellow, transversely elliptic, appendages very inconspicuous, almost absent. Male flowers 10-25; anthers yellow. Female flower: pedicel 2-4 mm, exserted from involucre; ovary glabrous; styles free, easily fallen; stigma slightly 2-lobed. Capsule exserted, nutant, 3-angular, ca. 3.5 × 3.5 mm, smooth; fruiting pedicel to 6 mm. Seeds globose, ca. 1.5 × 1.5 mm, light yellow, adaxially inconspicuously light brown striate; caruncle absent. Fl. and fr. Jun-Nov.

Sandy places near coasts. S Guangdong, Hainan, Taiwan [Cambodia, India, Indonesia, Japan, Laos, Malaysia, Myanmar, Philippines, Sri Lanka, Thailand, Vietnam; Australia, Pacific islands].

Euphorbia lingiana is only an extreme example, with a long root, of this species.