Taxonomic distinctions within several species groups have been perplexing. Research including extensive field studies have shown that in some groups this is because supposedly different species are actually indistinguishable and should be treated as a single species. In other groups, however, the species are clearly distinct but some of the characteristics that have been used historically to separate them are unreliable. New identification keys and descriptions that use reliable characters have been published. Because Acalypha includes both widespread, common species and rare species, understanding the taxonomy is vital for conservation and policy-making.
Research is underway to update the taxonomy of both genera.
This work will help biologists working to conserve tropical forests and will also shed light on the distributional processes that have led to both genera being found on five continents. Revised taxonomic treatments have been published or will appear in various regional floras, including The Flora of the Venezuelan Guayana , Flora de Nicaragua , The Flora of the Greater Antilles, and Flora Malesiana . Dr. Robertson is also collaborating with Chinese botanists on the treatment of subfamily Maloideae for the forthcoming English translation and updated edition of the Flora of China. A total of 29 species are recognized. K. R. Robertson has been studying this group for some time and had completed a taxonomic treatment of this family for the southeastern United States.