Perennial herbs, creeping or climbing. Stems 4-angled, brittle. Stems, leaf margins and petioles with recurved prickles, the whole plant tending to cling to clothing. Stipules similar to the leaves.
Leaves (and leaf-like stipules) in whorls of 4-8, petiolate. Flowers in axillary or terminal cymes, bisexual, usually 5-merous. Calyx reduced to a rim; teeth 0, not enclosed in an involucre. Corolla rotate to ± campanulate, greenish to yellow. Ovary 2-locular with 1 ovule per loculus. Fruit fleshy, glabrous,
consisting of two round, 1-seeded mericarps. Derivation of name: A name in Pliny for madder Worldwide: 60 species in the Mediterranean, Africa, temperate Asia and America Zimbabwe: 2 taxa. |
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