Abstract Phillipson, P.B. & L. Allorge (2016). A remarkable new species of Clerodendrum L. (Lamiaceae) from Madagascar. Candollea 71 : 117–126. In English, English and French abstracts. DOI : http://dx.doi.org/10.15553/c2016v711a14 A species new to science is formally described and named as Clerodendrum kamhyoae Phillipson & Allorge. It is the third species of Clerodendrum L. (Lamiaceae) to be described from Madagascar that combines a long slender corolla tube with cauliflory, attributes that are uncommon in the genus. The prolific production of flowers along the trunk of the new species is quite extraordinary. Its possible relationships with other species of the genus are discussed and certain aspects of its reproductive biology are described. We provide line drawings, photographs and a distribution map for the new species, as well as an assessment of its conservation status using IUCN Categories and Criteria.