Phycomycetes (Phytophthora spp. nov. and Pythium sp. nov.) associated with degrading mangrove (Rhizophora mangle) leaves

Abstract

Fungi of the genus Phytophthora were found to be associated with the initial stages of leaf litter decay of Rhizophora mangle L. and other Rhizophora species in estuarine and coastal marine waters. Phytophthora appears to be an important component of red-mangrove litter degradation systems throughout the tropics, which includes the Atlantic, Pacific, and Indian Oceans. The distributions of Phytophthora vesicula Anastasiou et Churchland and four new species of Phytophthora are discussed, as well as their occurrence in other tropical marine allochthonous spermatophytic leaf litter. The descriptions of the new species and varieties, Phytophthora bahamensis, P. epistomium, P. mycoparasitica, P. spinosa var. spinosa, and P. spinosa var. lobata, are presented.Pythium was rarely observed in the mangrove litter system, although one species, Pythium grandisporangium sp.nov., is described.