Chaos revisited: nomenclature and typifi cation of the Malagasy endemic Euphorbia subgenus Lacanthis (Raf.) M.G.Gilbert Thomas HAEVERMANS Germinal ROUHAN Muséum national d’Histoire naturelle, Département Systématique et Évolution, UMR 7205 OSEB CNRS/MNHN, Herbier Plantes Vasculaires, case postale 39, 57 rue Cuvier, F-75231 Paris cedex 05 (France)
[email protected] [email protected] Wilbert HETTERSCHEID Botanical Gardens, Wageningen University, Generaal Foulkesweg 37, NL-6703 BL Wageningen (The Netherlands)
[email protected] Marc TEISSIER Jardin botanique “Les Cèdres”, F-06230 Saint-Jean-Cap-Ferrat (France)
[email protected] Karim BELARBI Xavier AUBRIOT Jean-Noël LABAT Muséum national d’Histoire naturelle, Département Systématique et Evolution, UMR 7205 OSEB CNRS/MNHN, Herbier Plantes Vasculaires, case postale 39, 57 rue Cuvier, F-75231 Paris cedex 05 (France)
[email protected] [email protected] Haevermans T., Rouhan G., Hetterscheid W., Teissier M., Belarbi K., Aubriot X. & Labat J.-N. 2009. — Chaos revisited: nomenclature and typifi cation of the Malagasy endemic Euphorbia subgenus Lacanthis (Raf.) M.G.Gilbert. Adansonia, sér. 3, 31 (2) : 279-299. ABSTRACT Malagasy relatives of the Crown-of-Th orns (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 constitut- ing subgenus Lacanthis (Raf.) M.G.Gilbert. Th e chaotic taxonomy combined KEY WORDS Madagascar, with the poor state of preservation of most herbarium specimens makes the spiny euphorbias, systematic study of this huge genus a quite diffi cult task. Th is paper off ers a Lacanthis (Raf.) nomenclatural account of all the published names with a recapitulatory list M.G.Gilbert, nomenclature, citing all the accepted names in subgenus Lacanthis as a fi rst step towards the lectotypifi cation.