Two new taxa from Madagascar, belonging to the section Lomatophyllum Rowley of the genus Aloe L. (Xanthorrhoeaceae, Asphodelaceae), A. maningoryensis J.-P. Castillon, sp. nov. and A. alaotrensis J.-P. Castillon, sp. nov., are described here. The first one is morphologically intermediate between A. occidentalis (H. Perrier) Newton & Rowley from the west coast of Madagascar, and A. orientalis (H. Perrier) Newton & Rowley from the east coast; it grows on the highlands, in the forests near lake Alaotra. The second one, from the same area, is intermediate between A. propagulifera (Rauh) Newton & Rowley and A. socialis (Perrier) Newton & Rowley. Those two new species are particularly interesting because they connect together some morphological groups of Lomatophyllum and thus confirm the unity of the section.
Xanthorrhoeaceae, Aloe, Aloe sect. Lomatophyllum, Madagascar, new species.