Aquatic Mushrooms: Unraveling the Ecology, Evolution, and Biotechnology of Freshwater and Marine Macrofungi

Terrestrial mushrooms dominate mycology; their aquatic relatives are a fascinating and ecologically significant group. Psathyrella aquatica , the sole single‐gilled genus with underwater‐reported fruiting bodies, and marine‐dwelling genera such as Nia and Halocyphina illustrate how Basidiomycota radiated to aquatic environments. These freshwater, marine, and brackish aquatic fungi are principal nutrient cyclers, wood decayers, and symbionts of aquatic habitats, but their biology and ecology are poorly known. Herein, our current knowledge of their diversity, evolutionary adaptations such as floatation spores, halotolerant enzymes, and hydrophobic fruiting bodies, and their potential biotechnological applications is reviewed. Marine mushrooms are a source of bioactive compounds with reported antimicrobial and anti‐inflammatory activities, and their enzymatic profiles, adapted to saline or submerged conditions, suggest potential for bioremediation applications. With global warming, there is a need to research aquatic mushrooms not just to preserve biodiversity but also to tap their potential for green technology. This review synthesizes current knowledge on targeted research and conservation efforts for aquatic mushrooms. This information is essential for both understanding global biodiversity and advancing biotechnological innovations.