Comb bushmint

Mesosphaerum pectinatum (syn. Hyptis pectinata), the comb bushmint or 'sambacaitá', is an erect aromatic herb or subshrub of the Lamiaceae native to the warm Americas from southern Mexico through the Caribbean and Brazil, and naturalized in tropical Africa and Asia. Plants reach 0.5–2 m with quadrangular, finely pubescent stems and opposite, decussate leaves on short petioles. Leaf blades are ovate to ovate-lanceolate, 3–10 cm long, with serrate margins, sparsely pilose surfaces, and conspicuous oil glands giving a strong sweet, minty-balsamic fragrance. Inflorescences are slender axillary panicles with the small flowers crowded into one-sided, comb-like (pectinate) cymes, 1–3 cm long, subtended by small linear bracts—hence the epithet. Each flower has a 5-toothed campanulate calyx 2–3 mm long that lengthens in fruit, and a small bilabiate, pale violet to lavender corolla 3–4 mm long. The fruit is a set of 4 small smooth nutlets. Flowering occurs through the warm season; the species favours disturbed open ground.