Ainsliaea is a genus of perennial herbs, rarely subshrubs, in the family Asteraceae (order Asterales), first described by Augustin Pyramus de Candolle in 1838. The genus comprises approximately 50 species distributed across East Asia, the Indian subcontinent, and Southeast Asia, from Afghanistan and Pakistan eastward through India, Nepal, Bhutan, Bangladesh, China, Korea, Japan, and southward into Myanmar, Thailand, Vietnam, Indonesia, and the Philippines. China hosts the greatest diversity, with 40 species, of which 28 are endemic.
Plants are characteristically perennial herbs with leaves arranged alternately, frequently gathered into basal rosettes or clustered near the middle of the stem. Leaf blades vary widely in shape — linear, ovate, elliptic, or orbicular — with margins that may be entire, crenate, denticulate, dentate, or lobed. The flowering heads (capitula) are small and numerous, arranged in spikes, racemes, or panicles and sometimes nodding. Each head is discoid or radiate and contains only a few florets — typically (1–)3(–5) — which are bisexual and all fertile. The corolla of open (chasmogamous) florets is deeply and irregularly 5-lobed, with one slit distinctly longer than the others and the lobes reflexed and often coiled. Some species also produce closed, self-fertilizing (cleistogamous) florets. Fruits are ribbed achenes, glabrous or hairy, bearing a pappus of plumose (feathery) bristles. The chromosome number is 2n = 24 or 26.
The genus was monographed by Susana Freire in 2007 (Annals of the Missouri Botanical Garden 94: 79–191), the current authoritative revision. A synonym is Diaspananthus Miquel. Notable members include Ainsliaea acerifolia, with maple-like palmately lobed leaves, and Ainsliaea apiculata, a small-leaved species with deeply lobed blades.
Etymology
The Chinese name for the genus is 兔儿风属 (tù ér fēng shǔ), meaning roughly "rabbit-ear wind genus," a reference to the leaf shape of some species. The Latin genus name Ainsliaea was established by Candolle in 1838; the honoree is not recorded in the primary literature.
Distribution
Ainsliaea is native to a broad arc of Asia spanning Afghanistan, Pakistan, India, Nepal, Bhutan, Bangladesh, China, Korea, Japan, Myanmar, Thailand, Vietnam, Indonesia, and the Philippines. China is the center of diversity, with 40 of the roughly 50 known species, 28 of them endemic. The genus is absent from the Americas, Africa, and Australasia.
Taxonomy Notes
Ainsliaea was described by Augustin Pyramus de Candolle in Prodromus 7: 13 (1838) and placed in the family Asteraceae. The genus is synonymized with Diaspananthus Miquel. The most recent comprehensive revision is Freire (2007) in the Annals of the Missouri Botanical Garden (94: 79–191), the standard reference for species delimitation. GBIF places the genus in order Asterales, class Magnoliopsida. The chromosome complement is 2n = 24 or 26.
