Species delineation in the tree pathogen genus Celoporthe(Cryphonectriaceae) in southern Africa

The genus Celoporthewas first described when C. dispersawas discovered in South Africa associated with dieback and cankers on trees in the Myrtales. Four additional species were recently described from Eucalyptusand Syzygium cuminiin China as well as S. aromaticumand Eucalyptusin Indonesia. Inoculation trials have shown that all Celoporthespecies, including those that have not been found on Eucalyptusspecies in nature, are pathogenic to Eucalyptusand they are thus potentially threatening to commercial Eucalyptusforestry. New isolates, morphologically similar to Celoporthe, have been collected from S. legattiin South Africa and S. guineensein Zambia. Multigene phylogenetic analyses based on DNA sequences of the ITS region, TEF1α gene and two areas of the β-tubulin gene revealed additional cryptic species in Celoporthe. Phylogenetic data were supported by morphological differences. These resulted in the description of two previously unknown species of Celoporthe, namely C. fontanaand C. woodiana, for two of these cryptic groups, while the third group represented C. dispersa. These species all can readily infect Eucalyptusas well as several species of Syzygium, the latter of which are native to Africa.