Fabaceae - Taxonomy

Taxonomy

The Fabaceae are placed in the order Fabales according to most taxonomic systems, including the APG III system. The family includes three subfamilies:

• Mimosoideae: 80 genera and 3,200 species. Mostly tropical and warm temperate Asia and America. Mimosa, Acacia.
• Caesalpinioideae: 170 genera and 2,000 species, cosmopolitan. Caesalpinia, Senna, Bauhinia, Amherstia.
• Faboideae: 470 genera and 14,000 species, cosmopolitan. Astragalus, Lupinus.

These three subfamilies have been alternatively treated at the family level, as in the Cronquist and Dahlgren systems. However, this choice has not been supported by late 20th and early 21st century evidence, which has shown the Caesalpinioideae to be paraphyletic and the Fabaceae sensu lato to be monophyletic. While the Mimosoideae and the Faboideae are largely monophyletic, the Caesalpinioideae appear to be paraphyletic and the tribe Cercideae is probably sister to the rest of the family. Moreover, there are a number of genera whose placement into the Caesalpinioideae is not always agreed on (e.g. Dimorphandra).