Lamium L.
Annual or perennial herbs, often diffuse or decumbent; stems sometimes rhizomatous and creeping, but not stoloniferous. Lvs simple, crenate to dentate. Verticels crowded in dense axillary or, less commonly, terminal whorls. Bracts mostly similar to lvs. Calyx tubular or campanulate, 5-nerved, not gibbous at base, with 5 equal or subequal teeth. Corolla white to pink or purple, 2-lipped; upper lip hooded, densely hairy outside; lower lip with the main central lobe obcordate or obovate, with or without small lateral lobes. Stamens lying below upper lip; anther cells divergent. Style gynobasic. Nutlets ± trigonous, truncate at apex.
Key
4
Lvs incised-dentate; corolla tube without an obvious ring of hairs inside towards base
Lvs crenate or crenate-serrate; corolla tube with conspicuous ring of hairs inside towards base
40-50 spp., temperate Eurasia, N. Africa. Naturalised spp. 5.
