Atlas of the Acanthaceae of East Africa
Kew is providing expertise and collections-data towards an atlas of this diverse and important family in East Africa. This project will provide a good example of the ways in which accumulated herbarium data on plants can be used and disseminated to increase our knowledge of regional diversity and conservation priorities.
An image of Barleria usambarica
The Flora of Tropical East Africa (FTEA) programme and associated plant-diversity research projects in Kenya, Tanzania and Uganda, have resulted in the accumulation of large amounts of data on the region’s flora, most notably through the large herbarium collections amassed both within these countries and in their partner institutions in Europe and North America. The East African plant collections held at Kew are a particularly rich and important resource. However, access to these data can be difficult, both because the collections are distributed around the world and because they were mainly developed in the pre-digital age and so the vast majority of collection data are not available electronically. This project, led by the University of Copenhagen, therefore aims to bring together key institutions in East Africa and Europe to provide an example of the range of ways in which these data can be made more accessible and used to increase our knowledge of plant distribution and diversity.
The Acanthaceae (shrimp-plant) family was specifically selected for this mapping project as it has diversified in a wide variety of habitats in East Africa (c. 600 taxa in 50 genera), with high levels of local endemism and rare and/or threatened species. By mapping the individual species, total species diversity and distribution of the likely threatened species, the family can therefore be used as a proxy for identifying regional diversity hotspots and, potentially, plant conservation priorities in East Africa. It will also reveal useful information on biogeographical trends as well as identifying areas that have been under-studied and require further botanical survey.
Dr Henry Ndangalasi of the University of Dar es Salaam, Tanzania, and Dr James Kalema of Makerere University, Uganda, spent several months at Kew in 2007, databasing and geo-referencing all of Kew’s Acanthaceae collections from Kenya, Tanzania and Uganda using a Brahms database. They have carried out the same task on the collections at their own institutions plus those at the Natural History Museum in London, the East African Herbarium in Nairobi and the National Herbarium of Tanzania. Overall, an estimated 24,500 specimens are now catalogued in the Brahms database, representing the vast majority of our accumulated knowledge of the distribution of the Acanthaceae family in East Africa. Input and guidance has been provided by the two specialists on African Acanthaceae at Kew, Dr Kaj Vollesen and Dr Iain Darbyshire, since they were at the same time writing the account of the family for FTEA.
With FTEA Acanthaceae now published, the next stage is to update all the specimen identifications on the database according to the taxonomy detailed in that work. As part of this process, Dr Darbyshire visited the collections at Dar es Salaam in June 2008 and those at the East African Herbarium, Nairobi in August 2009; from the latter visit, over 500 identifications were updated in Brahms. Additional specimen data from recent (2006-2008) Kew-led expeditions to the Acanthaceae-rich areas of central and western Tanzania will also be added in to the database in the near future. Once the data are finalised, the individual species maps and the composite maps can be produced quickly according to a template already developed at the University of Copenhagen.
The large dataset amassed during this project will provide an excellent grounding for follow-up research, including formal conservation assessments of all Acanthaceae species in the region, which will contribute to a wider East African Plant Redlist.
Project partners and collaborators
Natural History Museum of Denmark, University of Copenhagen (overall project leader: Prof. Ib Friis)
University of Dar es Salaam, Botany Dept.
Makerere University, Kampala, Botany Dept.
Danish International Development Agency (DANIDA)
Bentham & Moxon Trust