Anemonastrum is a genus of flowering plants in the family Ranunculaceae, order Ranunculales. It comprises around 38 accepted species (per Kew's Plants of the World Online as of 2020) distributed across the temperate and subarctic zones of North America, Greenland, Europe, Asia, South America, and New Zealand — an unusually wide geographic range for a single genus.
The genus was segregated from the broadly circumscribed Anemone on the basis of chromosome number: Anemonastrum plants have a base chromosome number of x=7, whereas Anemone sensu stricto has x=8. In other respects the two genera are morphologically very similar — both are herbaceous perennials bearing solitary or few-flowered stems with deeply divided basal leaves and showy, petal-like tepals surrounding a central cluster of stamens and pistils. The generic name itself reflects this kinship: Anemonastrum is Latin for "somewhat like Anemone."
Well-known members include Anemonastrum narcissiflorum, a robust alpine species of European and Asian mountain meadows bearing clusters of white flowers; Anemonastrum canadense (Canada anemone), a widespread and vigorous wildflower of moist meadows and streambanks across North America; and Anemonastrum richardsonii, a small Arctic species named after the Scottish botanist John Richardson.
Etymology
The name Anemonastrum is a Latin compound meaning "somewhat like Anemone," formed from Anemone (the closely related genus) and the diminutive/comparative suffix -astrum. It reflects the strong morphological resemblance between the two genera while signalling their taxonomic distinctness.
Distribution
Anemonastrum species are native to temperate and subarctic regions across six continents and major island groups, including North America, Greenland, Europe, Asia (including alpine zones of the Himalayas and Central Asia), South America (primarily the Andes), and New Zealand. The genus favours open habitats such as alpine and subalpine meadows, tundra, and moist streamside vegetation.
Taxonomy Notes
Anemonastrum was separated from Anemone based on its base chromosome number of x=7, contrasting with x=8 in Anemone sensu stricto. Kew's Plants of the World Online recognised 38 species in the genus as of August 2020. The GBIF backbone records only 2 descendants, reflecting a different circumscription; users should consult Kew/POWO for the most current species count.
