Phylogenetic studies of Ephelis species from various locations and hosts in Asia

Ephelis japonica and E. oryzae are biotrophic fungi that form systemic epiphytic associations with warm-season grasses. Ephelis has been recognized as the anamorph of Balansia and Myriogenospora, and a synanamorph of Atkinsonella; all three genera belong to Clavicipitaceae (Ascomycota). The teleomorphs have not been detected for E. japonica and E. oryzae. Balansia oryzae had been regarded as the teleomorph of Ephelis oryzae, however, this teleomorphic name is not validly published for the teleomorph alone (Art. 59.6). We analyzed the sequences of the ITS1, ITS2 and 5.8S rDNA regions of 33 Ephelis isolates from Japan, Korea, China, Nepal and India. Phylogenetic relationships of these isolates were analyzed, together with other clavicipitaceous fungi for which sequences were obtained from GenBank. All Asian Ephelis isolates formed a single cluster, which comprised two subgroups. One subgroup had strong affinity with B. andropogonis, an epibiont of grasses in tropical regions of Asia. The second subgroup had strong affinity with B. discoidea, an epibiont of grasses in the Americas. A close relationship was also shown to B. asperata, another epibiont of grasses of tropical regions of Asia. Our results do not justify the separation of Asian Ephelis epibionts into E. oryzae and E. japonica. E. japonica, established in 1904, ten years prior to the name E. oryzae, is the appropriate name for the asexual Ephelis epibionts of warm season grasses of Asia.