Atropanthe


Atropanthe is a monotypic genus of flowering plants belonging to tribe Hyoscyameae of subfamily Solanoideae of the family Solanaceae.
The single species, Atropanthe sinensis is native to the temperate forests of S. Central China. It is a herbaceous perennial which bears a marked similarity to the related genus Atropa - whence the genus name Atropanthe.
Unlike Atropa, however Atropanthe bears a dry, pyxidial fruit, resembling a pot with a lid.

Description

A glabrous subshrub or perennial herb arising from thick rhizomes to a height of 0.8-1.5 m and bearing erect, terete or angled stems of a dark blue-purple colour, each bearing two or three green branches.
Leaves mostly paired, petiolate, entire, petioles 1-4.5 cm; leaf blades elliptic to ovate, 11-22 × 4–12 cm, papery, glabrous, bases cuneate, slightly decurrent, tips pointed.
Flowers greenish-yellow, borne singly in the leaf axils. Corolla circa 3.2 cm, 5-lobed, somewhat zygomorphic, tubular-campanulate, twice as long as calyx, 15-veined; lobes subequal, corolla aestivation quincuncial.
Stamens inserted in corolla tube, unequal, shorter than or equaling corolla; filaments circa 2 cm, unequal, circinnate in the bud and curved at flowering, inserted near the base of the corolla, pubescent at base; anthers somewhat heart-shaped, ventrifixed, 4-4.5mm dehiscing longitudinally. Disc orange, ringlike, slightly lobed.
Pedicel at time of flowering elongate, glabrous 1-2.5 cm. Calyx at flowering tubular-campanulate or somewhat urceolate, slightly inflated, somewhat bent, 15-veined, with 5 main veins, papery, glabrous, circa 2 cm; lobes subequal, deltate to rounded erose to ciliate, glabrescent.
Pedicel at time of fruiting barely thickened, 3-3.5 cm. Fruiting calyx hanging downward, the broad inflated base uppermost and the constricted but open mouth held below, conical, ovoid, or oblong, usually lantern-like/top-shaped, 2.5–3 cm in diameter, inserted abruptly on pedicel and easily detached from it after drying. Fruit a pyxidium, the downward-pointing operculum dehiscing to liberate seeds which fall, on ripening, through the downward-pointing opening of the bladder-like fruiting calyx. Pyxidium turbinate 1.8–2 cm in diameter, containing some 40-50 seeds.
Seeds brown, rectangular, somewhat compressed, circa 3 × 2.5 mm, the testa thick, bearing a wavy-netted pattern.

Range

An area encompassing NW Guizhou, W Hubei, SE Sichuan and NE Yunnan and including the Hengduan Mountains.

Habitat

Humid places, along ditches, forests; at altitudes of 1400–3000 m.

Medicinal use

Like all the other genera of the Solanaceous tribe Hyoscyameae, the genus Atropanthe is rich in tropane alkaloids - compounds possessing anticholinergic properties which are therapeutically useful in small doses and dangerously hallucinogenic in larger ones.
The roots of the single species A. sinensis are used in Chinese medicine">Chinese (language)">Chinese medicine for the relief of muscular spasm and pain.

Chemistry

Atropanthe sinensis contains the tropane alkaloids hyoscyamine and anisodine and also the pyrrolidine alkaloid bellaradine, a.k.a. cuscohygrine, and occurs also in the closely related genera Atropa, Anisodus and Przewalskia.

Translation of Chinese common name

The Chinese vernacular name for A. sinensis, 天蓬子 has been transliterated into Latin script both as tiān péng zi and tien pung tzu. An approximate pronunciation is "tien pong dzuu".
The name is composed of the individual characters 天 tiān "heaven"/"sky"/"day” 蓬 péng "disheveled/flourishing/vigorous/forming clumps" and 子 zi variously "son", "seed" and a nominalising suffix.
The two-character compound 天蓬 translates into English as "canopy.
天蓬子 in its entirety could thus, prosaically, indicate a vigorous and untidy, clump-forming plant, forming a canopy of foliage in which its seeds hang or are borne, unless 天 were translated in the more metaphysical sense of "heaven"/"heavenly", intended to suggest that the effects of consuming the plant could be perceived as somehow otherworldly - a suggestion compatible with the well-documented use in ancient Chinese Taoist practices of other Solanaceous plants as entheogens enabling the taker to "see spirits".

Botanical translations of 蓬 (péng)

A further complication in the translation of the plant name for Atropanthe 天蓬子 is that the character 蓬 has a number of botanical translations in its own right, yielding the meanings "type of raspberry", Korean mugwort and fleabane. The raspberry plant and Artemisia princeps, the Korean mugwort have in common the characteristic of being very vigorous plants and the mugwort is considered not only an edible plant but also a magical one, holding a prominent place in the story of the bear-woman, Ungnyeo - the foundational myth of the Korean nation. It may be that Atropanthe sinensis was perceived in China to share certain characteristics of these plants - possibly simply their vigour or rapidity of growth/potential invasiveness.

''A. mairei'' synonym for plant in different family

A potential source of confusion in regard to the monotypic status of this Solanaceous genus is the existence of the binomial Atropanthe mairei, which is listed by Kew as a synonym of Cyananthus flavus subsp. montanus .
Atropanthe mairei was identified by Lauener in 1978 as being Cyananthus albiflorus, which is now correctly known as C. flavus subsp. montanus