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A survey of myxomycete diversity on five islands of the Seychelles yielded 105 species and 10 infra-specific taxa, which included 89 species on La Digue, 66 on Praslin, 63 on Mahé, 31 on Curieuse and 4 on Félicité. Among these records, 64 species are new for the Seychelles and together with data from the literature, 143 species of myxomycetes are now known for all of the Seychelles. Most collecting on all five islands was carried out in low elevation areas. Forty-four species (73% of all specimens of myxomycetes) were found in low-elevation localities, and among these were Arcyria helvetica, Dictydiaethalium dictyosporum, Echinostelium paucifilum, Physarum aeneum, Ph. echinosporum, Reticularia olivacea, and Stemonaria longa. From 54 species of plants used by myxomycetes as substrates, eight species provided 63% of the specimens of myxomycetes, with most samples recorded from Calophyllum inophyllum. On the basis of substrate type, myxomycetes were distributed as follows: 37% of specimens were collected on dead wood and decaying palm stems, 16% on the bark and stems of living plants, 25% on ground litter, and 22% on aerial litter. A comparison of the assemblages of myxomycetes found in zones with different levels of human impact indicated that 84 species were found in forests, 74 in anthropogenic areas, and 62 in recreational coastal areas. The Seychelles provide a good background for a high level of myxomycete diversity, as a consequence of favorable climatic conditions and their location between Asia and Africa.

The checklist provided herein contains 143 species and infra-specific taxa of myxomycetes representing six orders, 12 families and 29 genera known from the Seychelles Islands. These records are the result of 878 field collections and 468 samples processed with the use of the moist chamber techinque. The overall study involved expeditions to the granitic group of islands Mahé, Praslin, La Digue, Curieuse, Félicité, and data from the literature for the coral Aldabra atoll. The taxonomic structure of the myxomycete biota for the islands studied indicates a predominance of members of the order Physarales (74 taxa). Th e main genera are <em>Physarum</em> (38 species and two varieties), <em>Didymium</em> (17 species), <em>Cribraria</em> (11 species), <em>Arcyria</em> (eight species) and <em>Stemonitis</em> (six species and two varieties). For all six islands only a single species of myxomycete (<em>Physarum crateriforme</em>) was shared in common. For the total assemblage of species recorded from all of the islands, 4% species were abundant, 12% species were common, 29% were found occasionally, 42% were rare, and 13% species had only a single record. The most abundant species were <em>Arcyria cinerea</em>, <em>A. denudata</em>, <em>Diderma effusum</em>, <em>Hemitrichia calyculata</em>, <em>Physarum compressum</em>, and <em>P. melleum</em>. Based on data from 50 different localities with 90 collecting plots, 32% of all specimens were associated with coastal vegetation, 30% with lowland localities, 19% with intermediate forests, 9% with riverine forests, 8% with mountain forests, and only 2% with mangrove swamps. In general, this annotated checklist clearly shows that isolated tropical islands can support a diverse assemblage of myxomycetes.

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