Description from Flora of China
Tumidinodus H. W. Li.
Subshrubs, epipetric or terrestrial, rhizomatous. Stems branched, branchlets sometimes angled. Leaves few, along stem, opposite, unequal in each pair; leaf blade puberulent to glabrescent, base narrowly cuneate to rounded. Inflorescences lax to dense, axillary, 2-8-flowered cymes; bracts 2, deciduous, opposite. Calyx actinomorphic, 5-sect from base; segments equal. Corolla white to yellowish, zygomorphic, inside with 2 arcuate projections abaxially; tube subtubular, gibbous abaxially near limb, longer than limb, 0.7-1.7 cm in diam.; limb 2-lipped; adaxial lip 2-lobed; usually shorter than abaxial lip; abaxial lip 3-lobed, lobes equal to unequal, apex rounded to obtuse. Stamens 4, adnate to corolla tube near middle, included; anthers basifixed, coherent in pairs, thecae slightly divergent, confluent at apex, dehiscing longitudinally; connective not projecting; staminode 1, adnate to adaxial side of corolla tube. Disc ringlike. Ovary linear, 1-loculed; placentas 2, parietal, projecting inward, 2-cleft. Stigma 1, terminal, disclike, undivided. Capsule straight in relation to pedicel, linear, much longer than calyx, dehiscing loculicidally to base; valves 2, straight, not twisted. Seeds with 1 subulate appendage at each end.
Three species: China, N Vietnam; all three species in China.
According to the protologue, Anna has 2 stigmas. A specimen from Chapa (N Vietnam), the type locality of A. submontana, has persistent, entire, and disclike stigmas. Tumidinodus H. W. Li was based on two specimens from SE Yunnan. An examination of the type (Wang Shou-zheng 879), as well as Fang Ding 25490 from Guangxi and a specimen
from N Vietnam (collector unknown), reveal that they belong to Anna submontana.