During routine surveys for possible fungal pathogens in the rapidly expanding plantations
of Eucalyptus and Cunninghamia lanceolata in China, numerous isolates of unknown species in the
genus Ceratocystis (Microascales) were obtained from tree wounds. In this study we identified the
Ceratocystis isolates from Eucalyptus and Cunninghamia in the GuangDong, GuangXi, FuJian and
HaiNan Provinces of South China based on morphology and through comparisons of DNA sequence
data for the ITS, partial β-tubulin and TEF-1α gene regions. Morphological and DNA sequence
comparisons revealed two previously unknown species residing in the Indo-Pacific Clade. These are
described here as C. cercfabiensis sp. nov. and C. collisensis sp. nov. Isolates of C. cercfabiensis
showed intragenomic variation in their ITS sequences and four strains were selected for cloning of
the ITS gene region. Twelve ITS haplotypes were obtained from 17 clones selected for sequencing,differing in up to seven base positions and representing two separate phylogenetic groups. This is the
first evidence of multiple ITS types in isolates of Ceratocystis residing in the Indo-Pacific Clade.
Caution should thus be exercised when using the ITS gene region as a barcoding marker for
Ceratocystis species in this clade. This study also represents the first record of a species of
Ceratocystis from Cunninghamia.