Format: ORAL

Paulo Henrique Gaem1,2 Eve Lucas3, Fiorella Fernanda Mazine4 Maria do Carmo Estanislau do Amaral1

1 University of Michigan, Ann Arbor, MI, USA 2 Universidade Estadual de Campinas, Campinas, SP, Brazil 3 Royal Botanic Gardens, Kew, Richmond, Surrey, UK 4 Universidade Federal de São Carlos, Sorocaba, SP, Brazil

Herbaria are the most important source of information for taxonomic work. Facilities and technologies available today, such as digitisation of collections and herbarium DNA sequencing, can help accelerate taxonomic decisions. Species complexes are a major factor preventing a better understanding of plant diversity in the tropics. In this context, we employed a multi-source pipeline to address limits among taxa of the Myrcia neoobscura species complex (Myrtaceae) using herbarium specimens. We collected morphometric traits from high-resolution images and analysed them with a clustering analysis, resulting in twelve morphological groups. We subsequently tested these groups with phylogenomics using molecular data obtained from herbarium specimens. Congruence between morphology and phylogenomics was observed in the following: Myrcia marliereana, M. neoobscura, and M. neoriedeliana, as currently circumscribed, represent two entities each, and M. excoriata can be split in three entities. We also investigated species geographic distributions and phenological patterns using herbarium specimens and their labels. The two species today recognised under M. neoriedeliana and M. neoobscura differ in flower seasonality, while two of the taxa currently under M. excoriata differ in both geographic distribution and flowering phenophase. The final species delimited in this work are morphologically diagnosable and geographically structured, and most of them are monophyletic according to the obtained phylogenetic reconstruction. The successful results of this work are based on the high-quality data obtained from museum specimens, and other herbarium-based investigations of species complexes are encouraged to accelerate the much-needed taxonomic resolutions in the tropics.