Phylogeny of Tribe Myrteae (Myrtaceae)
To set the context for Kew’s focus on Myrcia s.l., molecular phylogenetic studies were first focused on the largest tribe of Myrtaceae, the fleshy fruited and primarily Neotropical tribe Myrteae. It is within this tribe that baseline taxonomy is most lacking. Due to high morphological variation at all taxonomic levels, Myrtaceae in the Neotropics has a reputation as being a ‘difficult' family to identify even to the generic level. The traditional subtribal classification of Myrteae is unstable as are generic boundaries within. The objective of the Myrteae phylogeny project is to clarify internal relationships within the tribe and to provide a phylogenetic hypothesis for evolutionary relationships between as many as possible of the 48 genera recognised within it.
Initial results focusing on subtribal relationships were published in 2005 and 2007 and have demonstrated the paraphyly of traditional subtribes Myrtiinae and Eugeniinae, the monophlyly of the Myrciinae s.s. excluding Myrceugenia and the monophyly of a group of previously hard-to-place genera, Myrceugenia, Luma and one species of Blepharocalyx. Morphological studies in tribe Myrteae have been carried out in parallel to molecular research, macromorphological characters have been surveyed to find suitable morphological characters with which to interpret the phylogeny and better understand character evolution within it. The phylogeny is to be dated and subjected to further biogeographical analysis.
In 2009, in collaboration with personnel from the University of Ceará (Brasil), six further genera, several of previously anomalous position, were added to this study along with an increase in molecular markers. Sequences from this period were shared with collaborators at the University of Adelaide (Australia) concerned with hypothesizing and dating phylogenetic events at the family level. Funding from the REFLORA project (CNPq Brasil) will allow the Myrteae phylogeny project to be further developed and used as a basis for a new subtribal classification.
Key publications since 2006
- Biffin, E., Lucas, E.J., Craven, L.A. Ribeiro da Costa, I., Harrington, & Crisp, M.D. (2010) Evolution of exceptional species richness among lineages of fleshy-fruited Myrtaceae. Ann. Bot. 106(1): 79-93.
- Lucas, E.J., Harris, S.A., Mazine, F.F., Belsham, S.R., Nic Lughadha, E.M., Telford, A., Gasson, P.E. & Chase, M.W. (2007). Suprageneric phylogenetics of Myrteae, the generically richest tribe in Myrtaceae (Myrtales). Taxon 56: 1105–1128.
- Proença, C.E.B., Nic Lughadha, E.M., Lucas, E.J., & Woodgyer, E.M., (2006). Algrizea (Myrteae, Myrtaceae): A New Genus from the Highlands of Brazil. Syst. Bot. 31: 320–326.
Project partners and collaborators
University of São Carlos, Sorocaba, State of São Paulo
University of São João del Rei, State of Minas Gerais
Federal University of Ceará, State of Ceará
Royal Botanic Garden Edinburgh