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DescriptionAnnual or perennial herbs or shrubs to 5 m. Inflorescence composed of 3-11 whorls per shoot, each whorl dense, spherical, axillary, many-flowered; bracts leaf-like; bracteoles linear, spine-tipped. Calyx 8-10-toothed; teeth usually rigid, spine-tipped. Corolla tubular, 2-lipped, white, covered with orange hairs (rarely white); tube with 1-3 transverse fringes of hairs inside; upper lip entire; lower lip 3-lobed. Stamens 4. Nutlets glabrous.