Description from Flora of China
Chingyungia T. M. Ai.
Herbs, annual, hemiparasitic. Leaves opposite, entire. Flowers solitary in axils of bracts or congregated into racemes or spikes; bracts leaflike in shape, margin often with pointed or setose teeth, rarely entire. Calyx campanulate; lobes 4, upper 2 larger than lower. Corolla tube tubular, gradually expanded upward; limb dilated, 2-lipped; lower lip patent, base 2-plicate, apex 3-lobed; upper lip galeate, compressed, slightly shorter than upper lip, margin revolute, apex obtuse. Stamens 4, didynamous, enclosed by galea; anthers connivent, locules equal in size and base conically pointed, bearded along slit after dehiscence. Ovules 2 per locule. Stigma capitate, entire. Capsule ovoid, slightly compressed, straight or oblique, loculicidal, apex obtuse or tapered. Seeds 1-4, oblong, large, smooth.
About 20 species: Northern hemisphere; three species in China.
Melampyrum taxonomy is quite complex, and the number of recognized species varies with authors. There is a great deal of variation in certain characters, particularly in bract morphology. Chinese plants were once classified into 8 species, which are here treated as 2, in addition to 1 newly recorded species.