A novel Cryphonectria species (Cryphonectriaceae, Diaporthales) discovered on Eucalyptus, including insights into the mating biology of the genus.

A new Cryphonectria species, Cry. eucalypticola, is identified on Eucalyptus in North Sumatra, marking the first report of the genus in the Southern Hemisphere on Myrtales.

• Why it matters: Understanding the diversity and biology of Cryphonectria species is crucial due to their role as significant plant pathogens with ecological and economic impacts worldwide.
• What they did: Researchers used DNA sequencing, phylogenomic analyses, and morphological observations to identify the fungus, tested its pathogenicity on Eucalyptus, and examined its mating biology, revealing it as a homothallic species.
• The result: Cry. eucalypticola is mildly pathogenic and likely an endophyte, with its discovery expanding knowledge of Cryphonectria diversity and mating systems, and highlighting its potential ecological role.