Miller, J.S. & M. Gottschling (2017). Generic transfers in Malagasy Boraginales. Candollea 72 : 329–332. In English, English and French abstracts.
Recent molecular data have demonstrated convincingly that the Old World genus Hilsenbergia Tausch ex Meisn. (Ehretiaceae) is nested within the New World genus Bourreria P. Browne. Thus, 13 new combinations are required to accommodate the endemic Malagasy species in Bourreria. Additional studies have demonstrated that Heliotropium sect. Orthostachys R. Br. (Heliotropiaceae) is not closely related to the rest of the genus and should be segregated as Euploca Nutt. Three species that occur in Madagascar fall into this group, including one endemic that requires a new combination.