Chaos revisited: nomenclature and typification of the Malagasy endemic Euphorbia subgenus Lacanthis (Raf.) M.G.Gilbert

Malagasy relatives of the Crown-of-Thorns (Euphorbia milii Des Moul.) are well known worldwide for their ornamental value. Malagasy taxa account for almost 10% of the genus Euphorbia L., with 110 accepted names constituting subgenus Lacanthis (Raf.) M.G.Gilbert. The chaotic taxonomy combined with the poor state of preservation of most herbarium specimens makes the systematic study of this huge genus a quite difficult task. This paper offers a nomenclatural account of all the published names with a recapitulatory list citing all the accepted names in subgenus Lacanthis as a first step towards the revision of the group.