The family Rhizophoraceae includes around 135 tropical (especially Old World) species of trees and shrubs placed in around 15 genera (Mabberley 2008). Although some are mangroves (around 18 species in four genera: Bruguiera, Ceriops, Kandelia, and Rhizophora), others are not--and some species from other families are mangroves as well. Thus, although Rhizophoraceae includes a number of important and widespread mangrove species, with viviparous seeds and aerial roots, it should not be thought of as "the mangrove family". The principal genera in Rhizophoraceae are Bruguiera, Carallia, Cassipourea, Ceriops, Crossostylis, Pellacalyx, and Rhizophora (Mabberley 2008). Rhizophora is the most conspicuous genus in tropical, coastal mangrove ecosystems (Cerón-Souza et al. 2010).
Both molecular phylogenetic analyses and analysis of floral structures indicate that the sister group to Rhizophoraceae is Erythroxylaceae (best known for the Erythroxylum species from which cocaine is derived) (Setoguchi et al. 1999; Matthews and Endress 2011 and references therein)
Juncosa and Tomlinson (1988) provided a thorough review of the taxonomic history of Rhizophoraceae to 1988. For up-to-date estimates of numbers of genera and species for Rhizophoraceae or other flowering plant families, as well as current information on relationships among flowering plant families, see the Angiosperm Phylogeny Website.
