An exploratory study of species richness and dynamics in the cultivable mycobiota of Palmaria palmata

This study presents the first exploratory analysis of the cultivable fungal communities associated with the red alga Palmaria palmata and their temporal dynamics over one year. The fungal isolation strategy employed two culture media - a non-specific Wickerham medium and a specific “ P. palmata” medium - coupled with two incubation temperatures (12 °C and 27 °C), and a differentiation between epiphytic and endophytic fungi. This experimental design yielded 298 fungal isolates. Through morphological observations and molecular techniques, 142 fungal taxa were identified. The cultivable fungal diversity associated with P. palmata was dominated by members of the phylum Ascomycota, with the classes Dothideomycetes, Eurotiomycetes and Sordariomycetes, and the genera Cladosporium , Penicillium and Aspergillus emerging as the dominant groups. This fungal diversity exhibited significant seasonal variation, with culture conditions - including incubation temperature and culture medium composition - influencing the diversity and composition of the cultivated fungi obtained.