Mariana de Oliveira Bünger

Myrtaceae in the Atlantic forest: their role as a ‘model’ group

Myrtaceae is one of the richest families in the Atlantic Forest, a priority biodiversity hotspot that continues to be highly threatened, subject to rapid urbanisation and high levels of resource exploitation. Authors have suggested that individual lineages can be used as models to study biome evolution and ecology and to provide data for conservation planning in these areas. Here we review how Myrtaceae fit the ‘model’ criteria and examine the family’s distribution throughout the Brazilian Atlantic Forest answering the questions: What is the ecological representation of Myrtaceae in the Atlantic Forest?; What is the current taxonomic situation of Myrtaceae in the biome?; What is the current phylogenetic understanding in the family?; Does the historical timeframe of the lineage coincide with that of the biome?; Can Myrtaceae be used to discuss species diversity hotspots within the Atlantic forests?; What is the role of Myrtaceae in conservation strategy? And finally, Can Myrtaceae be used as a ‘model’ taxon? The concept of the ‘model taxon’ is also discussed. The review concludes that taxonomic and phlyogenetic understanding in Myrtaceae are rapidly increasing, giving hope that taxonomic stability, easy species identification and management are realistic in a way unthinkable only a few decades ago. Myrtaceae function well as a ‘model’ within the Atlantic forest but fit some criteria better than others. Taxa can qualify as ‘models’ representing different times and pressures in the history of a given biome; each tells its own story. For future ‘model’ group studies to have maximum impact and implementation for evolutionary studies and conservation strategy, synthetic studies of multiple ‘model’ groups using multiple approaches are required; only then can a predictive understanding of past and future processes in the biomes concerned, be glimpsed.

Myrtaceae throughout the Espinhaço Mountain Range of centraleastern Brazil: floristic relationships and geoclimatic controls

Although biological surveys and taxonomic revisions provide key information to ecological and evolutionary studies, there is a clear lack of floristic and phytogeographic studies of the mountainous regions of Brazil, which harbor some of the most threatened plant ecosystems on the planet. Myrtaceae has been reported to be one of the most important families in the upland areas of Brazil, as well as in the Atlantic Forest Domain. In this study, we investigated the floristic composition of Myrtaceae throughout the Espinhaco Mountain Range and adjacent highlands of central-eastern Brazil, testing the following hypotheses: floristic similarity increases with geographic proximity; and species distribution is affected by geoclimatic variables. We performed statistical analyses using a database containing records of 199 species in 19 areas and of their respective geoclimatic variables. We also performed ordination analysis using non-metric multidimensional scaling (NMDS), the first and second axes of which explained 69% and 78% of the variation, respectively. The NMDS analysis demonstrated that variations in the Myrtaceae flora are highly sensitive to geoclimatic variables and geographic proximity. The NMDS ordination also showed a predominantly south-north gradient, as did the cluster analysis. This gradient was highly correlated with variations in rainfall and temperature, which are also associated with the three domains that coincide with the Espinhaco Mountain Range.

Myrtaceae no Parque Estadual do Itacolomi, Minas Gerais, Brasil

Resumo Apresentamos neste trabalho o estudo taxonomico das Myrtaceae ocorrentes no Parque Estadual do Itacolomi (PEIT), uma Unidade de Conservacao localizada no estado de Minas Gerais, no sul da Cadeia do Espinhaco. A vegetacao da area e formada por florestas montanas tropicais e campos rupestres. Para o tratamento taxonomico foram elaboradas descricoes, comentarios, chaves de identificacao e ilustracoes. Foram realizadas coletas de setembro 2009 a dezembro de 2010 e foram revisados os herbarios BHCB, OUPR, RB e VIC. A familia esta representada no PEIT por 11 generos e 44 especies: Blepharocalyx (1 sp.) , Calyptranthes (1 sp.) , Campomanesia (4 spp.) , Eugenia (4 spp.) , Marlierea (3 spp.) , Myrceugenia (2 spp.) , Myrcia (20 spp.) , Myrciaria (1 sp.) , Plinia (1 sp.) , Psidium (3 spp.) e Siphoneugena (4 spp.) . Palavras-chave : Cadeia do Espinhaco, floristica, taxonomia. Myrtaceae in the Parque Estadual do Itacolomi, Minas Gerais, Brasil Abstract This work aims identify and characterize species of Myrtaceae occurring in the Itacolomi State Park (PEIT), located in the state of Minas Gerais, in southern Espinhaco Range. The vegetation in the area comprises tropical montane forests and “ campos rupestres ” . Descriptions, comments, identification keys and illustrations are presented. Collections were made in the PEIT from September 2009 to December 2010 and the BHCB, OUPR, RB and VIC herbaria were revised. The survey resulted in 44 species occurring in the PEIT, belonging to 11 genera: Blepharocalyx (1 sp.) , Calyptranthes (1 sp.) , Campomanesia (4 spp.) , Eugenia (4 spp.) , Marlierea (3 spp.) , Myrceugenia (2 spp.) , Myrcia (20 spp.) , Myrciaria (1 spp.) , Plinia (1 spp.) , Psidium (3 spp.) and Siphoneugena (4 spp.) . Key words : Espinhaco Range, floristic, taxonomy.

Circumscription and synopsis of Eugenia section Speciosae Bünger & Mazine (Myrtaceae)

Abstract A new section of Eugenia (Myrtaceae) is described, segregate from Eugenia sect. Phyllocalyx. Phylogenetic studies suggest that Eugenia sect. Phyllocalyx as traditionally delimited is paraphyletic. To maintain the monophyly of each of the sections in Eugenia s.l., we herein opt to circumscribe a new section and recognize six taxa in sect. Speciosae, which has a distribution mostly in southeastern Brazil and northern South America. Nomenclatural notes are made and a taxonomic key is provided for the species of the section.

Resolving Species Delimitations in the Eugenia involucrata Group (Eugenia sect. Phyllocalyx - Myrtaceae) with Morphometric Analysis

Abstract Eugenia (Myrtaceae) is the largest genus of Neotropical Myrtaceae comprising ca. 1,100 species. Eugenia sect. Phyllocalyx is a group that is morphologically characterized by the presence of leaf-like bracts and showy sepals. During the taxonomic review of the section, a complex of species closely related to E. involucrata, including Eugenia calycina, E. cavalcanteana, E. suffrutescens, E. stricta, E. neoformosa, E. incertissima, and E. chodatii, was identified.We carried out a morphometric analysis and taxonomic review of these species. Measures of 12 vegetative and floral characters were sampled from 77 herbarium specimens, encompassing the morphological variability and the geographic distribution of the species. A principal component analysis (PCA) was carried out to test the morphological discontinuity within the complex. Separate morphological groups were not revealed by the PCA and therefore we propose E. involucrata to be a single, highly variable species. A recircumscription and nomenclatural update of E. involucrata are presented, including seven lectotypifications and 17 synonyms, of which seven are new.