Diversity and ecology of arenicolous marine fungi inhabiting the Tottori Sand Dunes beach

Abstract

Ascospores accumulated in sea foam and fruit bodies of arenicolous marine fungi attached to sand grains were collected regularly from the beach at the Tottori Sand Dunes and observed for about 2.5 years. Twenty-two species belonging to 13 genera (21 species of Ascomycota ［including four asexual morphs］ and one of Basidiomycota) were identified based on morphological analysis of the spores and fruit bodies. The mycoflora identified at Tottori included many species reported from coasts on the Sea of Japan, and so was different from that found on the Pacific coasts of Japan. Among these species, 15 belonging to nine genera were classified into three different types (the year-round type, the warm season type, and the cold season type) according to the appearance of spores in the sea foam. The species within each type had their own temperature-dependent properties in terms of mycelial growth and sporulation. The coexistence on the beach of species with different properties probably causes seasonal fluctuations in the species found in sea foam. Assimilation testing of various substrates (driftwood/seaweed/feather/heavy oil) used by arenicolous marine fungi demonstrated several different preferences. These different substrate preferences probably drive the diversity of arenicolous marine fungi species inhabiting the beach.