VII. Subfam. Nepetoideae (Dumort.) Luerss. (1882).
VII. 2. Tribe Mentheae Dumort. (1827).
VII. 2. D. Tribe Mentheae: Incertae Sedis
DescriptionSlender perennial herb; leaves cordate, toothed, long-petiolate; inflorescence secund, of 1-3-flowered cymes, shortly pedunculate to sessile, in axils of reduced bracts, forming an elongate, terminal thyrse; bracteoles inconspicuous; calyx often purple-tinged, cylindrical to campanulate, strongly 2-lipped, 5-lobed, (3/2), posterior lip with median lobe broadly ovate, rounded at apex, slightly spreading and weakly decurrent on tube at base, lateral lobes shortly triangular-acuminate, anterior lip longer, with sinus between lobes shorter, tube slightly gibbous at base, 15-nerved, annulate within, below throat; corolla white, strongly 2-lipped, 5-lobed (4/1), posterior lip of 4 short, rounded, subequal lobes, anterior lip longer, with lobe slightly concave, rounded, tube narrowly cylindrical, straight, exserted from calyx, and abruptly expanded above, exannulate; stamens 4, didynamous, long-exserted, ascending under upper lip, later becoming slightly divergent, posterior pair longer at early anthesis, anterior pair apparently extending later, anthers 2-thecous, thecae elliptic, widely divaricate, confluent at apex; style exserted; stigma-lobes subequal, subulate, spreading; disc 4-lobed, anterior lobe elongate; nutlets oblong-ovoid, smooth to finely striate, with small, elliptic areole. One species, H. debile (Hemsl.) C.Y. Wu, with several varieties, China.
Native to:36 China
Heterolamium C.Y. Wu, Acta Phytotax. Sin. 10: 254 (1965).
© Royal Botanic Gardens, Kew