<i>Friedmannodendron rodriguesiana</i>, a new segregate of <i>Dombeya</i> Cav. (Dombeyoideae, Malvaceae), endemic to Rodrigues

<i>Dombeya rodriguesiana</i> F.Friedmann is an endemic species to Rodrigues (Mascarene Archipelago, Indian Ocean). This species faces severe threats and is currently represented by at least two living individuals. We sequenced a second sample of this species to confirm that its phylogenetic placement renders <i>Dombeya</i> Cav. paraphyletic and, thus, its placement in <i>Dombeya</i> needs revision. The second sample was extracted from a cultivated clone of the last wild individual of <i>D. rodriguesiana</i>. Sequences from this individual for six markers (one nuclear, five plastid) were analyzed using the largest molecular dataset available on Dombeyoideae and Bayesian inference and maximum likelihood methods. Study of all known herbarium material of <i>D. rodriguesiana</i>, and other relevant material, allowed for a new morphological evaluation and description. Our results demonstrate that <i>D. rodriguesiana</i> is closely related to the Malagasy endemic genus, <i>Andringitra</i> Skema. We found that the unique combination of characters of a persistent epicalyx with a persistent perianth provides the synapomorphy for these two sister taxa, independent of the significant morphological differences between them (e.g. flower size, number, arrangement, sex expression). Furthermore, we describe useful field characters to differentiate <i>D. rodriguesiana</i> from the superficially similar <i>D. ferruginea Cav</i>. To maintain a meaningful classification that reflects monophyletic groups in the Dombeyoideae, we propose the establishment of a new genus and combination to accommodate this rare species.