Bombacaceae

Bombacaceae were long recognised as a family of flowering plants or Angiospermae. The family name was based on the type genus Bombax. As is true for many botanical names, circumscription and status of the taxon has varied with taxonomic point of view, and currently the preference is to transfer most of the erstwhile family Bombacaceae to the subfamily Bombacoideae within the family Malvaceae in the order Malvales. The rest of the family were transferred to other taxa, notably the new family Durionaceae. Irrespective of current taxonomic status, many of the species originally included in the Bombacaceae are of considerable ecological, historical, horticultural, and economic importance, such as balsa, kapok, baobab and durian.

Recent phylogenetic research has shown that Bombacaceae as traditionally circumscribed (including tribe Durioneae) is not a monophyletic group. Bombacaceae is no longer recognized by the Angiosperm Phylogeny Group I 1998, II 2003 and Kubitzki system 2003 at the rank of family, the bulk of the taxa in question being treated as subfamilies Bombacoideae and Helicteroideae within family Malvaceae sensu lato. A close relationship between Bombacaceae and Malvaceae has long been recognized but until recently the families have been kept separate in most classification systems, and continue to be separated in many references, including the reference work in classification of flowering plants: Heywood et al. 2007 and Takhtajan 2009, but have been lumped together in Angiosperm Phylogeny Website.

Heywood et al. say "although closely related to Malvaceae, molecular data supports their separation. Only pollen and habit seem to provide a morphological basis for the separation." On the other hand they say: "One approach is to lump them [the families in the core Malvales, including Bombacaceae] all into a 'super' Malvaceae, recognizing them as subfamilies. The other, taken here, is to recognize each of these ten groups as families."

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