The inclusion of Akeassia in Grangea (Asteraceae) and description of a new species from Gabon: Grangea ogoouensis

Abstract

• The discovery of a new Gabonese species of Asteraceae leads us to reevaluate the distinction between the genera Grangea Adans. and Akeassia J.-P. Lebrun & Stork. The differences between the two genera proving unreliable, Akeassia is included in Grangea, resulting in the new combination Grangea grangeoides (J.-P. Lebrun & Stork) Beentje & O. Lachenaud. A key to the ten species of Grangea is presented, as well as complete morphological descriptions for the three species occurring in Gabon: Grangea grangeoides, Grangea maderaspatana (L.) Desf., and and the new species Grangea ogoouensis O. Lachenaud & Beentje. The new species differs from Grangea grangeoides by its pinnatifid lower leaves and more numerous pappus-bristles, and from Grangea maderaspatana by its free pappus bristles and smaller phyllaries. It appears to be endemic to Gabon, and its conservation status is assessed as “Vulnerable”.