Trematosphaeria pertusa.
Image Credit: Manfred Binder

Trematosphaeria pertusa (Pers.: Fr.) Fuckel (Trematosphaeriaceae) is reported from freshwater habitat. Anamorphs are not known. Trematosphaeria is characterised by medium to large sized ascomata with peridia composed of small compressed cells, clavate to cylindrical bitunicate asci, a trabeculate hamathecium in a gelatinous matrix and reddish-brown ellipsoid to fusoid transversely septate ascospores.
Fungi play a major role in the decomposition of wood and leaf litter in forest ecosystems. Many of the dominant decayers are Basidiomycota producing extracellular enzymes involved in wood decay, which require aerobic conditions. Some Ascomycota and other anamorphic fungi degrade large amounts of submerged woody debris in lakes and streams, and their fungal biomass makes up to 75% in such habitats. The form of submerged decomposition has been classified as soft rot, which is also the prevalent decay mode of Ascomycota in terrestrial habitats. The genome data from Trematosphaeria pertusa will help characterizing aquatic wood decay in environments that do not offer oxygen in abundance.