Two new Malagasy species of genus Piper L. (Piperaceae): Piper malgassicum and Piper tsarasotrae and their phylogenetic position

We describe here two new species of genus Piper L. from Madagascar: Piper malgassicum and Piper tsarasotrae, the species names referring to the currently known distribution areas. These two species contribute, at least in part, to the production the local voatsiperifery pepper, probably mixed together with P. borbonense and are, therefore, economically relevant as spices. We used a selected set of characters (those more easily observable on herbarium samples) for a Principal Component Analysis, to assess the relative distance between both species, including in the analysis the autochthonous species of Piper known from Africa and Madagascar. In order to check the identity and to assess the phylogenetic position of the two species, we also sequenced the chloroplast gene ndhF and the trnL intron and the nuclear gene G3PDH. On the basis of these results, we show here the relationships between these two new Piper taxa and the most closely related species within the genus (excluding P. heimii and P. pachyphyllum, for which only morphological characters were available).