Abstract
All published names of Croton from Madagascar, the Comoros, and the Mascarenes are treated here. We indicate which names are currently accepted (123 native species and 1 introduced), which ones we consider to be heterotypic synonyms (188), which ones are doubtful (25), and which ones should be excluded (5). We newly designate lectotypes for 108 names, and epitypes for C. anisatus Baill., C. nobilis Baill., and C. submetallicus Baill. A total of 133 names are newly treated as synonyms. One new combination is made, Croton basaltorum (Leandri) P.E.Berry for C. antanosiensis var. basaltorum Leandri, and one new name is proposed, Croton toliarensis B.W.vanEe & Kainul. for C. tranomarensis var. rosmarinifolius Radcl.-Sm.