1) Dilleniid dicot family 2) Family clethraceae 3) White-alder family 
The Clethraceae are a small family of flowering plants in the order Ericales, native to warm temperate to tropical regions of Asia and the Americas, with one species also on Madeira. The family comprises two genera, Clethra and Purdiaea. In the past, most botanists included only Clethra in the family, but recent research has shown Purdiaea, previo...
(from the article `Ericales`) ...family) consists of 3 genera and 14 species and occurs in northern South America, Central America, the West Indies, and on the coastal plain of ...
[n] - coextensive with the genus Clethra
family Clethraceae noun coextensive with the genus Clethra