The Clethraceae are a small family of flowering plants in the order Ericales, composed of two genera, Clethra and Purdiaea, with approximately 75 species.
[2] They are native to warm temperate to tropical regions of Asia and the Americas, with one species also on Madeira.
[citation needed] 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.
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