Prunella

Perennial herbs; branchlets 4-angled, hairs simple. Leaves opposite, petiolate, entire to pinnatifid, margin serrate or entire. Inflorescence terminal, cylindrical, spike-like, with (3–)6-flowered cymes in the axil of broad, sessile bracts; internodes of inflorescence usually hidden by bracts. Calyx 2-lipped, abaxial lip deeply 2-lobed, with lobes ciliate, adaxial lip truncate with 3 sharp, almost obsolete teeth-like lobes; corolla 2-lipped, abaxial lip spathulate, with 2 narrow lateral lobes and a broadly spathulate medial lobe, adaxial lip broadly oblong, shallowly 2-lobed; stamens 4, fertile, inserted at different levels toward the throat of the corolla, anthers with 2 fertile locules, exserted; ovary deeply 4-lobed, style gynobasic, stigma terminal, 2-fid. Mericarps oblong-ovoid, c. quadrangular in section.