|Clethra arborea flowers|
The Clethraceae are a small family of flowering plants in the order Ericales, composed of two genera, Clethra and Purdiaea, with approximately 75 species. They are native to warm temperate to tropical regions of Asia and the Americas, with one species also on Madeira.
In the past, most botanists included only Clethra in the family, but recent research has shown Purdiaea, previously placed in the closely related family Cyrillaceae, is more closely allied to Clethra.
- Angiosperm Phylogeny Group (2009). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III" (PDF). Botanical Journal of the Linnean Society. 161 (2): 105–121. doi:10.1111/j.1095-8339.2009.00996.x. Retrieved 2013-06-26.
- Christenhusz, M. J. M. & Byng, J. W. (2016). "The number of known plants species in the world and its annual increase". Phytotaxa. Magnolia Press. 261 (3): 201–217. doi:10.11646/phytotaxa.261.3.1.
- (Anderberg & Zhang 2002).
- Anderberg, A. A. & Zhang, Z. (2002). Phylogenetic relationships of Cyrillaceae and Clethraceae (Ericales) with special emphasis on the genus Purdiaea. Organisms, Div. & Evol. 2: 127–137.