MEM 118 C07-Endemism & importance of collections for revision of Dichorisandra.

(No reviews yet) Write a Review
08/11/2020 02:11:05

This purchase only includes chapter 7 of this title.

The Neotropical genus Dichorisandra is the largest of the subtribe Dichorisandrinae, being characterized by poricidal or functionally poricidal anthers and arillate seeds. Species belonging to Dichorisandra occur mainly in the understory of forests, but a few species are rupicolous and heliophytes. In a still unpublished taxonomic revision realized in 2008 for the genus, the authors reduced the 63 published binomials to 30 species. A better understanding of the genus was allowed by intense field studies and collection efforts, especially in botanically poorly known areas of eastern and northeastern Brazil. Many of the collected plants were cultivated. This combination of intensive field collections and cultivation of the plants led to the recognition of 24 new species; four of them were first collected by our group after 1999. This study confirmed the previously insufficient knowledge of the distribution of Dichorisandra, particularly in northeastern Brazil. Thus, about 50% of the new species occur in the state of Bahia. Regarding diversity and endemism of the genus, our study demonstrates the importance of the Atlantic rainforest sensu stricto, which is considered one of the priority areas for biodiversity conservation in the world. We also demonstrate the extreme importance of intensive field collections for a better understanding of biodiversity. This is true not only for the Amazon, but also for much smaller areas of the Brazilian Atlantic rainforests, where many new species still wait to be discovered. Phylogenetic analysis of the genera with species occurring in these regions should only be undertaken after taxonomic studies, as otherwise the results are dubious due to insufficient sampling.