Clethra | |
---|---|
Clethra arborea flowers | |
Scientific classification | |
Kingdom: | Plantae |
(unranked): | Angiosperms |
(unranked): | Eudicots |
(unranked): | Asterids |
Order: | Ericales |
Family: | Clethraceae |
Genus: | Clethra L. |
Species | |
Between 30-70; see text. |
Clethra is a genus of between 30-70 species of flowering shrubs or small trees. It is one of two genera in the family Clethraceae (the other being Purdiaea). The species may be evergreen or deciduous, and all bear flowers in clusters or inflorescences.
They are distributed from temperate to tropical climates in eastern and southeastern Asia, Malesia, Central America, northern South America, the southeastern United States, and one species (C. arborea) on the island of Madeira.
The number of species accepted varies between different authorities depending on taxonomic interpretation, but with a recent trend to reduce the number recognised as distinct; the recent Flora of China has cut the number accepted for China from 35 to 7 species, and the USDA only recognises two in the United States, synonymising C. tomentosa with C. alnifolia. The following is a selection: