- Source: Costus louisii
Costus louisii is a critically endangered species of plant endemic to Gabon.
Costus louisii was first described by Hiltje Maas-van de Kamer and Paul Maas in 2016. A.M. Louis collected the first and only specimen of Costus louisii obtained from the wild. Costus louisii has only been found in a small area, and its habitat appears threatened by human actions.
Costus louisii resembles Costus afer in appearance.