2.5.20 Rhytidhysteron bruguierae (Figure 7)

Rhytidhysteron bruguierae occurring on decaying Bruguiera wood, is phylogenetically related to the species R. mangrovei and R. thailandicum based on 18 S, 28 S rDNA and TEF- 1α genes (Dayarathne et al. 2020a). Morphologically, R. bruguierae differs from the two species in having a red epithecium and thicker exciple (Kumar et al. 2019; Thambugala et al. 2016). Base pair differences of TEF- 1α gene between R. bruguierae and R. mangrovei / R. thailandicum were over 3 % and were regarded as sufficient to warrant description of a new taxon (Jeewon and Hyde 2016). The type species of Rhytidhysteron is R. brasiliense which has no available sequences in GenBank (Spegazzini 1881). It is essential to obtain a culture of the type species to validate the taxonomic position of R. bruguierae and other species.