Species diversity of fleshy fruited tribes Myrteae and Syzygieae are highest in Conservation International priority biodiversity areas, habitats disappearing rapidly under human pressure. Diversity in the traditional genera of Myrcia s.l. (tribe Myrteae) peaks in the Brazilian Atlantic rainforest and cerrado (Myrcia, Marlierea, Gomidesia), the Amazon (Marlierea) and the Caribbean (Calyptranthes). Species of Syzygium (tribe Syzygieae) peak in Sundaland (Indonesia).
Kew’s Myrcia s.l. specimen database to date comprises c.15,000 georeferenced records, including Kew’s complete and extensive collection of c. 8000 specimens and complete or partial specimen record holdings from other institutions including the New York Botanical Garden, the Rio de Janeiro Botanical Garden, the botanical garden in Santo Domingo and the Research Institute for Development – Cayenne, French Guiana. Kew’s Bornean Syzygium are databased and a georeferenced database of African Syzygium is in preparation.
Newly published Myrcia s.l. and African Syzygium species, or those under monographic review are systematically subject to full or preliminary IUCN criteria-based conservation using geo-referenced specimen data. c. 300 such assessments have been produced and once compiled can be harnessed in a variety of ways.
Full IUCN conservation assessments for all African Syzygium are incorporating results from specimen based niche modeling of Syzygium species habitats.
In conjunction with Kew’s GIS team, Myrcia s.l. specimen data has been used to identify species occurring in the Atlantic Forest biome. Statistical analysis demonstrated Myrcia s.l. diversity to be an indicator of total tree species diversity in the Atlantic rainforest. Preliminary conservation assessments were generated for all species then habitat distribution modelling and complementarity analyses were used to determine areas of likely high concentration of Atlantic Forest endemics and threatened endemics. These areas were prioritised and ranked according to levels of vegetation quality, protection and threat.
Areas of endemism of Myrcia s.l. have also been examined using ordination techniques to determine similarity of distribution sub-areas and establishment of phytogeographically meaningful, phylogenetically independent areas of endemism for use in biogeographical studies providing greater understanding of the evolutionary history of this large and complex group over continental South America and the Caribbean.
A project in conjunction with the Federal University of Goiás (Brazil) uses specimen data as the basis for studying the evolution of reproductive patterns of American Myrtaceae, linking phenological, distributional and phylogenetic data. A further part of this project focuses on a sub-group of Myrcia s.l. and incorporates species distribution modeling to under various climatic change scenarios to predict environmental response of these species and their ecosystems to future climate change.
This project promotes ecological understanding of conservation priorities in biomes supporting exceptional levels of biodiversity, that are home to indigenous and other traditional communities and that provide ecosystem services and resources worth millions of US$ per year. These biomes are also substantial carbon sinks, sequestering millions of tonnes of carbon annually.