New species and records of Coryneum from China

Following the abandonment of dual nomenclature and the implementation of single-name nomenclature for pleomorphic fungi, Coryneum was considered to have priority over Pseudovalsa and was recommended for use. Currently, Coryneum is the only genus in the family Coryneaceae (Diaporthales). However, DNA sequence data are lacking for most Coryneum species, and no detailed phylogenetic analyses of the genus are yet available. In the present study, fresh Coryneum samples were collected from chestnut (Castanea) and oak (Quercus) trees in China and morphologically compared with accepted Coryneum species. Based on morphological characteristics, they were identified as one known species, Coryneum castaneicola, and three novel species described here as C. gigasporum, C. sinense, and C. suttonii. Conidial dimensions and host association were considered major characters for species distinction. The previously unknown sexual morph of C. castaneicola is reported and described. A phylogenetic analysis of nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) and large subunit (28S) sequence data of a representative matrix of Diaporthales confirmed Coryneaceae to represent a monophyletic clade. A phylogenetic analysis of a combined sequence matrix containing the ITS-28S rDNA, the translation elongation factor 1-α (TEF1α), and the second largest subunit of the RNA polymerase II (RPB2) of the four Chinese and four additional European Coryneum species was performed, confirming the distinctness of these novel species.