Format: ORAL

Fabin A. Michelangeli1, Frank Almeda2, Lucas Bacci3, Eldis R. Bcquer4, Lo-Paul Dagallier1, Walter S. Judd3, Renato Goldenberg5, Darin S. Penneys6, Monique Romeiro-Brito3, Lucas C. Majure3

1 The New York Botanical Garden, Bronx, NY, USA 2 Frank Almeda, California Academy of Sciences, San Francisco, CA, USA 3 University of Florida, Gainesville, FL, USA 4 Jardín Botánico Nacional-Universidad de la Habana, La Habana, CP, Cuba 5 Universidade Federal do Paraná, Curitiba, PR, Brazil 6 University of North Carolina Wilmington, Wilmington, NC, USA

The tribe Miconieae (Melastomataceae) comprises ca. 1900 species of Neotropical mostly shrubs and trees. For most of the 20th century between 17 and 22 genera were accepted in most treatments, and another ca. 12 were often recognized in the tribe. Phylogenetic analyses, first with a few genes and more recently with hundreds of genes, recover Miconia (the largest genus with close to 1100 species in its old definition), as paraphyletic with all other genera embedded within it. Moreover, only four traditionally recognized are recovered as monophyletic, with some, like Leandra and Ossaea, recovered in at least a dozen clades each. A search for diagnostic characters that would allow recognition of a manageable group of smaller genera have proven futile due to a series of factors: 1-node stability and support, 2-changes in resolution with the addition of taxa, 3-well conserved and diagnostic characters being impractical for taxonomy (e.g. micromorphological features of seeds or internal anatomy), 4-well-defined and supported groups contain many taxa with reversals to plesiomorphic conditions rendering diagnostic characters unusable, and 5-well-supported and diagnosable clades are embedded in larger grades. Based on these factors we have proposed an expanded Miconia as the only genus in the tribe. Miconia s.l. is the seventh largest genus of flowering plants, and notably the only one among the 10 largest whose native range is restricted to the Neotropics. Recognizing Miconia s.l. highlights an extraordinary radiation that occurred in a relatively short amount of time. While the advantages of recognizing a single genus outweigh the disadvantages, this decision has some drawbacks. These include the size, making it unwieldy for monographic work, and subsumation of endemic genera that may impact their utility in conservation. We will discuss how these issues are shared among megadiverse genera and address different strategies for tackling them.