Background and Aims Herbaria are the most important source of information for botanical taxonomic work. Technologies available today, such as digitisation of collections and herbarium DNA sequencing, can help accelerate taxonomic decisions in taxonomically challenging groups. Here we employ an integrative pipeline relying exclusively on herbarium sheets to investigate species boundaries in the Neotropical Myrcia neoobscura complex (Myrtaceae).
Methods We collected morphometric trait data from high-resolution images of herbarium specimens and analysed it using hierarchical clustering. We posteriorly tested the obtained morpho-groups with phylogenomics using the Angiosperms353 probe kit. By collecting phenological and geographic data from specimens and their labels, we also built phenological histograms and Ecological Niche Models to investigate ecological differences amongst taxa.
Key Results Current circumscriptions of Myrcia arenaria, Myrcia neoglabra and Myrcia neoregeliana are confirmed in this study. Conversely, the four pieces of evidence together support Calyptranthes langsdorffii var. grandiflora, Marlierea regeliana var. parviflora and Marlierea warmingiana as separate from Myrcia marliereana, Myrcia neoriedeliana and Myrcia neoobscura, respectively, contrary to arrangements proposed by previous authors. Integrated analyses also support the separation between Myrcia excoriata and two similar, undescribed taxa.
Conclusions Our data reveal the need for major changes in the systematics of the group, with recognition of 12 species. Successful delivery of the study aims was possible due to obtaining robust, high-quality data from museum specimens. We emphasise the importance of maintaining botanical collections physically and digitally available for taxonomic work and advocate their use to accelerate taxonomic solutions of tropical species complexes under a holistic approach. This is urgent, given the paucity of funds for fieldwork in face of habitat
Less...