1. Tetragonia Linnaeus, Sp. Pl. 1: 480. 1753; Gen. Pl. ed. 5, 215. 1754.
New Zealand spinach [Greek tetra, four, and gonia, angle, in reference to the shape of the fruit]
Nancy J. Vivrette
Herbs [subshrubs], annual or perennial, succulent, glabrous, pilose, or papillate. Roots fibrous. Stems prostrate [subscandent], semiwoody at base. Leaves cauline, alternate, usually petioled; stipules absent; blade flat, margins entire to slightly sinuate or shallowly lobed. Inflorescences: axillary clusters of 2-3 flowers or flowers solitary, sessile or peduncled; bracts absent. Flowers bisexual or unisexual, inconspicuous, 5[-10] mm diam.; calyx campanulate, adnate to ovary, angled, winged, or horned; calyx lobes [3-]4-5[-7], green or yellow adaxially; petals and petaloid staminodia absent; nectary absent; stamens 1-20, perigynous; pistil 3-10-carpellate; ovary inferior [half inferior], [1-]3-10-loculed; placentation apical; ovule 1 per locule; styles 3-10; stigmas 3-10. Fruits nutlike [drupaceous], angled, indehiscent; horns [2-]4-6[-7]. Seeds 1-10, light brown, ± reniform, arils absent.
Species 60 (1 in the flora): introduced; South America, e Asia, Africa, Pacific Islands (New Zealand), Australia.