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References Medicinal Plants utilisation and BENOIST, J. (1995): La plante-médicament, entre ses conservation in the Small Island usages et ses témoins. – Ecologie humaine VIII(2) : 53-61. States of the SW Indian Ocean - GSPM. (2011): Liste rouge des plantes vasculaires with particular emphasis on endémiques de Madagascar. – IUCN SSC Madagas- car Plant Specialist Group. Mauritius MACFARLANE, J. & ALPERS, M. (2010): National Poli- Ameenah Gurib-Fakim cy for an Integrated Health System and Local Imple- mentation: the Case of Papua New Guinea and the Nasioi. – Human Organization 69(4): 387-398. Introduction MERAL, P. & REQUIER-DESJARDINS, D. (2006) : La Plants are known to be primary sources of all medi- gestion durable de l’environnement à Madagascar : cines in the world and continue to provide man- enjeux, opportunités et contraintes. – Économie rurale kind with new remedies. More than 80% of the 294-295: 4-8. Available at: http://economierurale.re- world’s population in the world still depend on vues.org/index891.html. traditional medicine for their primary health care MINISTERE DES EAUX ET FORETS. (1997): Décret n° 97-2000 portant adoption de la Politique forestière (WHO 1992). Natural products and their deriva- Malagasy du 2 octobre 1997. – Antananarivo, Jour- tives represent more than 50% of all drugs in clini- nal officiel de la République de Madagascar, p. 2324- cal use in the world (CRAGG & NEWMAN 2000). 2348. Higher plants contribute no less than 25% of the MONTAGNE, P. & RAMAMONJISOA, B. (2006) : Poli- total. Other drugs are derived from animals and tiques forestières à Madagascar entre répression et microorganisms. Therefore the possibilities for de- autonomie des acteurs. – Économie rurale 294-295: veloping new drugs from forest resources should 9-26. Available at : http://economierurale.revues.org/ feature in any calculation of their true worth. All index894.html the 119 plant-derived drugs used worldwide come RESOLVE. (2005): Evaluation et perspectives des trans- from fewer than 90 out of the 250,000 plant species ferts de gestion des ressources naturelles dans le cadre du Programme Environnemental 3. – Antananarivo, that have been identified DE( SMET 1997) The po- Rapport final de synthèse, 55p. tential for discovering more new chemical entities REPUBLIQUE DE MADAGASCAR. (1987): Arrêté In- is there. terministériel n°2915/87 portant conduite de The flora of the South West Indian Ocean belongs l’exploitation des produits accessoires des forêts du 7 to one of the global hotspots. To this date only two septembre 1987. – Journal officiel de la République de internationally recognised medicinal plants have Madagascar, p. 2092-2098. emerged from this part of the world – the Mada- REPUBLIQUE DE MADAGASCAR. (1995): Madagascar: rapport de pays pour la conférence technique interna- gascan Catharanthus roseus and Centella asiatica. tionale de la FAO sur les ressources phytogénétiques Yet the potential for the discovery of new entities (Leipzig,1996). as well as standardised extracts is enormous. REPUBLIQUE DE MADAGASCAR. (1996): Loi n°96-025 This paper presents the general situation of the relative à la gestion locale des ressources naturelles medicinal plant resources and their regulation in renouvelables du 30 septembre 1996. the Small Islands States of the South-West Indian Julie Le Bigot • AVERTEM, Faculté des sciences Ocean with particular emphasis on Mauritius. pharmaceutiques et biologiques, Département de botanique • 3, rue du professeur Laguesse, 59000 Flora of the Small Island States of the Indian Lille, France • email: [email protected] Ocean The flora of the Comoros Islands, which are geo- graphically close to the African continent, tends to show greater affinity to that of the continent, whereas the floras of the Seychelles and the Mas- carenes (Mauritius, Reunion and Rodrigues) are highly specialised and rich in endemics. Page 29 May 2012 Flora of the Comoros entity (ADJANOHOUN ET AL. 1983a, GUEHO 1988). The entire flora of the Comoros archipelago is es- Mauritius has 7 phanerogames, which are endemic, timated to contain some 2.000 species and a close while Reunion Island has 5 and Rodrigues has 3. examination reveals a high degree of endemism. With respect to the endemic species, Mauritius Taxa from the Comoros illustrating the affinity to has around 300 or 60-65% of the indigenous flo- the African flora are for example Alangium salvii- ra, while Rodrigues has around 50 or 55% of its folium ssp. salviifolium, Tabernaemontana coffe- flora. There are 671 species of indigenous flower- oides, Saba comoriensis, Combretum coccineum, ing plants recorded in Mauritius of which 311 are Cycas comoriensis, Phyllanthus comoriensis, Nux- endemic (Mauritius has 8 endemic plant genera) ia congesta, Tambourissa sp., Norhonia sp., Pep- and 150 are endemic to the Mascarene Archipela- eromia sp., Piper sp., Mimusops comoriensis, and go. Seventy-seven of these indigenous species are Weinmannia bojeriana. classified as extinct. Of the extant flowering plants ADJANOHOUN ET AL. (1982) identified 120 medici- about 35% are classified as threatened as per the nal plants, out of which 2 were endemic to the Co- IUCN criteria (BACHRAZ & TEZOO 1997). Recent moros: Tambourissa leptophylla and Helichrysum classifications have revealed the following: 141 sp. species are Critically endangered, 55 are Endan- gered, and 98 are Vulnerable. This recent estimate shows that at least 95 of the 141 Critically Endan- gered species have less than 50 known adults in the wild (FLORENS 2007). FIGURE 1 shows the histori- cal development in forest cover on Mauritius. Recent studies of lower plants have shown there to be about 207 taxa consisting of 89 genera of moss- es and 59 genera of hepatics (TIXIER and GUEHO 1997). There are about 200 species, subspecies and varieties of pteridophytes of which 13 species are endemic and 40 are extinct. Among the interesting indigenous species in Mauritius we find the fol- lowing: Diospyros tesselaria, Cassine orientale, Foetidia mauritiana, Stadmania oppositifolia, Ter- minalia bentzoe, Protium obtusifolium, Eugenia FIGuRe 1. Native forest loss in Mauritius (1773-1997). fasciculate, Erythroxylum sideroxyloides, Scutia myrtina amongst others. Flora of the Mascarenes [Mauritius, Rodrigues Rodrigues (Mru.) indigenous flora is also char- (Mru) and Reunion (Fr.)] acterised by a high degree of endemism. Accord- The Mascarene Islands are made up of three islands, ing to STRAHM (1989), the island has 36-38 taxa which have never been connected to the continental of endemic flowering plants but many of the in- mainland. The elements making up the indigenous digenous species have now become extremely rare flora have been introduced to the islands via ma- and are on the verge of extinction. Among them rine currents, trade and cyclonic winds, jet streams are Zanthoxylum paniculatum, Gouania legua- and marine and terrestrial birds during emigration. tii, Dombeya acutangula, Hibiscus liliiflorus and CADET (1977) presented the phytogeographical Antirhea bifurcata, which have all been reduced to analysis of the Mascarene Islands and reported that only a few individuals. Among the species, which 70% of the phanerogams come from Madagascar have been surveyed recently, and considered to be and the African continent, 8% are of oriental ori- more or less extinct are: Abrotanella rhynhocarpa, gin, 12% are of indopacific origin or cosmopolitan, Euphorbia daphnoides, Peperomia hirta, Syzygium while the remaining 10% are endemics. Phytogeo- balfourii amongst others. graphically, the Mascarenes can be considered an Reunion Island (Fr.) is the youngest of the is- Page 30 May 2012 lands of the Mascarenes. The island is entirely (1983a) identified 102 plants out of which 8 were volcanic and still has an active volcano claimed to indigenous to the Mascarene region (MAURITIUS & be 500,000 years old. The island is well placed to RODRIGUES). During a survey carried out between receive wind-borne seeds and has been colonised 1990-1994 (GURIB-FAKIM ET AL. 1995-1997), it partly by exotic plant materials. Nonetheless, the was found that reliable information is obtained island is still blessed with some interesting indige- mostly from persons aged 55 to 70 years, suggest- nous species like Foetidia mauritiana, Securinega ing a gradual erosion of the traditional knowledge. durissima, Cossigna pinnata, Cassine orientale Nonetheless, over 600 plants used medicinally amongst others. were collected and documented in the course of the study. More than 12% of the plants for which use Flora of the Seychelles was documented are endemic to the South West In- The Seychelles archipelago located to the North dian Ocean. East of Madagascar and discovered in the 17th century, encompass some forty islands and granitic It is also worth pointing out that local inhabitants islets. The flora is a model in itself because of its collect most of the medicinal plants from the for- high degree of specialisation and its rich diversity ests and that they often are unable to correctly iden- of highly endemic species. It has a few taxonomic tify them. Whilst forest collection is not legal, it is curiosities, for example Lodoicea maldivica which difficult for the authorities to control the collection is a unique endemic palm tree with a unique and of plants. Many of the used plants are becoming unusual shape growing in the Valley of May and extremely rare and whilst efforts are being made Praslin. It is the largest seed in the plant kingdom towards their safeguard, for some plants it may be and takes 7 years to ripen and germinate. The tree too little too late. There is always the underlying itself takes 25 years to reach the adult stage and fear that several species may become critically en- to produce flowers and seeds. The granitic island dangered due to over-collection. presents a real floristic refuge. The rocks and boul- It is interesting to note that whilst the Mauritian ders making up these islands are among the oldest population is made up of immigrants who have on this planet (650 millions years).