Malpighiales
Recent Achievements
Collections (2001-2005)
The average accession rate in the Malpighiales Herbarium Section (after it was established in 2002) was c. 2,350 specimens per year, and the number of sheets loaned to other institutions averaged c. 700 per year. The section is curated to a high standard and visitors were given professional curatorial support (total 20 long-term visitor months).
The focal point of active accessioning of herbarium material was the need for full generic representation for molecular studies of Achariaceae sensu lato, Euphorbiaceae sensu stricto, Phyllanthaceae, Salicaceae sensu lato and selected smaller Malpighiales families. As a result, samples were added to the Kew DNA bank and sequences added to GenBank (especially increased representation of Euphorbiaceae sensu lato, now including 56 of 59 Phyllanthaceae genera and of Achariaceae sensu lato, now including 9 of 12 Oncobeae / Lindakerieae genera).
The Herbarium collection of the Malpighiales Section has been continually recurated according to most recent taxonomic revisions. Recuration of all ‘Flacourtiaceae’ genera has been completed. Other extensive projects were East African and Madagascan Euphorbia, South East Asian Macaranga, East African Clutia, Croton and Phyllanthus, as well as the newly described genera of tribe Hippomaneae.
Types of all taxa of Euphorbiaceae sensu lato from India and 650 types of Violaceae databased and imaged; 800 types of African Euphorbia sensu lato and 400 types of South American Croton imaged and databased; imaging and databasing of type specimens and other selected specimens ongoing.
Herbarium specimens were added to collection through active liaising with other institutions and fieldtrips to Brunei, Madagascar, Mayotte (Comoro Islands; Territorial Collectivity of France), Sri Lanka and Vietnam. For example, fresh material suitable for DNA sequencing of Archileptopus from its only known locality was obtained by liaising with Herbarium of Nanning, Guixhou province, China, and fresh material of monotypic endemic Oreoporanthera from the alpine region of New Zealand by liaising with LANDCARE.
Baseline Plant Diversity Research (2001-2005)
The electronic (DELTA) morphological datamatrix and illustrated interactive keys to the Families and Genera of Malpighiales including Euphorbiaceae sensu lato (Centroplacaceae, Euphorbiaceae sensu stricto, Pandaceae, Phyllanthaceae, Picrodendraceae and Putranjivaceae), Achariaceae sensu lato, Salicaceae sensu lato and Ochnaceae have been launched and are now available on the internet at www.kew.org/herbarium/keys/malpigs. In Euphorbiaceae sensu lato, for example, 89 characters can be used to identify the c. 350 genera of this group (see project: Interactive Key to the Genera of Malpighiales).
New taxa were described as they came to our attention, including the two new genera Plagiocladus and Radcliffea and new species in Phyllanthus, Suregada and Wielandia. New combinations were made in Flueggea, Phyllanthus and Wielandia. A revision of Antidesma (Phyllanthaceae; Euphorbiaceae sensu lato, 56 species) in Malesia and Thailand was published.
Overviews of the systematics of Euphorbiaceae sensu lato in Madagascar as well as Euphorbiaceae sensu lato and Malpighiales world-wide were published in a more accessible format.
Following the split of Euphorbiaceae sensu lato and the incongruencies between molecular results and previous circumscriptions and classifications of Phyllanthoideae, a new classification of Phyllanthaceae was produced (in press).
The Flora treatment of Antidesma (Phyllanthaceae; Euphorbiaceae sensu lato) for Thailand (18 species) and a revision of Margaritaria for Malesia were published.
Contributions were made by the Malpighiales Team to Flacourtiaceae (S. Zmarzty) for the Mount Kinabalu checklist and to the Euphorbiaceae sensu lato accounts in two Cameroonian checklists edited by Martin Cheek and Yvette Harvey.
Comparative Plant Biology (2001-2005)
A number of phylogenetic studies in Malpighiales at different taxonomic levels were carried out and their results published.
At family level, molecular phylogenetics of “Flacourtiaceae” were studied, resulting in the combination of part of this family with Achariaceae sensu lato on the one hand, and with Salicaceae sensu lato on the other hand.
Molecular phylogenetics of Phyllanthaceae and Euphorbiaceae sensu stricto were investigated and four papers published in journals with high impact factors (2.4 and 4.2), totalling 74 printed pages.
Molecular phylogenetics of tribe Phyllantheae was studied for the first time with surprising results and consequences for the taxonomy of the group (see project: Molecular phylogenetics of tribe Phyllantheae (Phyllanthaceae; Euphorbiaceae sensu lato)).
Infragenerically, the molecular phylogenetics of Madagascan Euphorbia subgenus Lacanthis was studied in the course of a PhD project at MNHN Paris, co-supervised and co-authored by Kew staff (see project: Phylogenetics and Conservation of Madagascan Euphorbia (Euphorbiaceae)).
The occurrence of polyhydroxyalkaloids in Suregada (Euphorbiaceae) has been confirmed and data gathering for a comprehensive survey in Euphorbiaceae sensu stricto concluded (see project: Polyhydroxyalkaloids in Euphorbiaceae sensu stricto).
A broad survey has been carried out of the wood anatomy of all Malpighiales families that have wood. The most promising characters for identification/phylogenetic studies have been identified, data gathering for the initial paper concluded and a talk was given at the Malpighiales symposium at the IBC Vienna 2005 and at the 6th Pacific Regional Wood Anatomy Conference in Kyoto in December 2005 (see project: Wood anatomy of Malpighiales).
Colleters in Erythroxylaceae were surveyed in the light of the very close relationship of the family with Rhizophoraceae that was found with DNA sequence data.
Population genomic projects were initiated to study the genetic basis of adaptation and species differentiation in the two related European taxa Populus alba (white poplar) and P. tremula (European aspen) (NERC and Royal Society grants to Christian Lexer, Austrian Science Foundation (FWF) postdoctoral fellowship to Marcela van Loo to work with C. Lexer). The results were presented in three papers (two higher impact) and indicate that hybrid zones will be useful for ‘admixture mapping’ of adaptive or detrimental trait differences among these related species (see projects: Molecular genetic analysis of a barrier to gene flow between two ecologically divergent Populus species; Introgression of abiotic stress response genes across hybrid zones in Populus; Testing the role of ecological selection and clonal reproduction in hybrid zone persistence in European Populus).
The new alkaloid Antidesmone, initially isolated from the phyllanthoid Antidesma, was found in other members of the tribe but not in less closely related taxa.
Strong participation at major conferences: the International Botanical Congress 2005, Vienna, Austria (one Kew poster, co-authored three talks on Malpighiales, organised Malpighiales symposium), and the 5th biennial meeting of the Systematics Association in 2005 in Cardiff (two talks on Phyllanthaceae), Botany 2004, in Snowbird, Utah, USA (co-authored two talks on Malpighiales families) and the 17th AETFAT meeting 2003 in Ethiopia (one paper on Phyllanthus).
Successful PhD theses of Malpighiales students: Thomas Haevermans on Madagascan Euphorbia (MNHN Paris; supervised by P. Hoffmann); Hashendra Kathriarachchi on Phyllanthaceae and Phyllantheae phylogenetics (Univ. Vienna; P. Hoffmann and M.W. Chase, (see projects: Molecular phylogenetics of Euphorbiaceae sensu lato; Molecular phylogenetics of Tribe Phyllantheae (Phyllanthaceae; Euphorbiaceae sensu lato); Phylogenetics and Conservation of Madagascan Euphorbia (Euphorbiaceae)).
Successful MSc theses of Malpighiales students: Bakolinantenaina Andrianaivoravelona on Madagascan Phyllanthus (Univ. Antananarivo; P. Hoffmann).
Sustainable Utilisation of Plant Resources (2001-2005)
Kew is currently investigating the phenolics of Passifloraceae, that have a range of beneficial properties including anti-inflammatory activity. Over 100 species of Passiflora and related genera have been analysed and differences in the quantities of the phenolics in the cultivated passion flowers and wild accessions have been detected. Other research is being undertaken on the medicinal properties of a range of species from Malpighiales genera including Phyllanthus (Phyllanthaceae), Salix (Salicaceae) and Viola (Violaceae).
Conservation and Environmental Monitoring (2001-2005)
Conservation assessments for all newly described or revised taxa were published, including 152 IUCN conservation assessments of Madagascan Euphorbia carried out by Thomas Haevermans while on a SYNTHESYS grant at RBG Kew (available at: www.redlist.org). IUCN ratings were assigned to all 69 taxa of Antidesma (Phyllanthaceae; Euphorbiaceae sensu lato) in Malesia and Thailand.