Description from Flora of China
Herbs perennial, rarely annual. Stems erect or prostrate. Leaves long petiolate at stem base, petiolate or sessile upward, entire, pinnate. Verticillasters in dense capitula or spikes, or widely spaced; bract margin acute serrate or spinescent, rarely entire. Calyx tubular or campanulate-tubular, straight or slightly curved, 15-veined, 2-lipped, 5-toothed; teeth subequal or sometimes middle tooth of upper lip wider than lateral teeth, sinuses with a thickened fold. Corolla blue-purple, pink, or violet, rarely white, slender basally, dilated at throat, 2-lipped; upper lip straight or slightly curved; lower lip 3-lobed, middle lobe largest. Stamens 4, posterior 2 longer than anterior 2; anthers glabrous, rarely hairy, cells 2, divaricate at nearly 180°. Style apex equally 2-cleft. Nutlets oblong, smooth, sometimes mucilaginous.
About 70 species: alpine and semidry regions mainly in temperate Asia, with a few in Europe, one in North America; 35 species in China.
Closely related to Nepeta but calyces with a thickened fold between the teeth.