Mémoire
| Résumé : | Orchidaceae have been regarded as one of the most intriguing and, for this reason,attractive plant families for systematic. However, taxonomy, phylogeny andevolutionary processes are still poorly documented in many orchid genera.Tridactyle Schlechter belongs to the Angraecoids, one of the most complex groups ofthe Orchidaceae family, which must be taxonomically treated. The last revision wasconducted by Summerhayes in 1948 and since then, a lot of species have been addedto this genus, rending it deprecated.A previous master thesis showed that the species Tridactyle tridactylites, one of themost common among this genus and placed in the section D by Summerhayes (1948),is polyphyletic. By this work, this specie is constituted by three groups, based onmolecular markers. However, it was still unknown if it is possible to discriminatebetween these groups from morphological traits.The aim of the present work is therefore to elucidate the taxonomic state of thisspecie. For that purpose, we have included samples of the species related to T.tridactylites.Three of the others species belonging to the section D are recognized in this study: T.brevicalcarata, T. lisowskii and T. nanne-ritzkae. The species T. minutifolia is also distinctof T. tridactylites.Morphological traits have been discovered to discriminate the three groups of Leguil(2011). The monophyly of T. tridactylites is therefore recovered, and the two othergroups are described as probable new species, T. sp. nov. A and T. sp. nov. B.One of the species previously placed in synonymy with T. tridactylites, T. kindtiana, ismorphologically different from T. tridactylites and need to be revalidated at thespecies rank. |
