Description from Flora of China
Brachiostemon Handel-Mazzetti; Sinoboea W. Y. Chun.
Herbs, perennial, epipetric or terrestrial, rhizomatous. Stems simple or branched. Leaves few, along stem, opposite, equal to unequal in a pair; leaf blade puberulent to woolly, base rounded to cordate. Inflorescences lax, axillary, few- to many-flowered cymes; bracts 2, opposite. Calyx actinomorphic, 5-sect from base or near base; segments equal. Corolla blue to purplish, zygomorphic, inside bearded, outside oblique, campanulate, not swollen, shorter than limb, 2.2-8 mm in diam.; limb 2-lipped; adaxial lip 2-lobed; usually shorter than or occasionally equalling abaxial lip; abaxial lip 3-lobed, lobes equal or subequal, apex rounded. Stamens 2, adnate to abaxial side of corolla tube near base, included; anthers dorsifixed, coherent, thecae divaricate, confluent at apex, dehiscing longitudinally from straight or arcuate slits; connective not projecting; staminodes 2(or 3), adnate to adaxial side of corolla tube. Disc inconspicuous or ringlike. Ovary ovoid to ovoid-conical, 1-loculed; placentas 2, parietal, projecting inward, 2-cleft. Stigma 1, terminal, capitate, undivided. Capsule straight in relation to pedicel, narrowly oblong, slightly to 2 X longer than calyx, dehiscing loculicidally to base; valves 2 or 4, spirally twisted. Seeds unappendaged.
About 11 species: China, Malaysia, E Myanmar, Thailand, Vietnam; five species in China.