Distribution of the Genus Ceratocystiopsis (Ascomycota, Ophiostomatales) on Conifers in Norway, With Description of Four New Species

The genus Ceartocystiopsis includes ascomycetes fungi belonging to the Ophiostomatales that are not well recognized in the world. Described species so far have been found mainly in association with bark beetles in the Northern Hemisphere. The aims of this study were therefore to survey of distribution of species of Ceratocystiopsis associated with bark beetles infesting Picea abies and Pinus sylvestris in Norway. Adults for 22 different bark beetle species were collected from 13 stands in Norway. During this study, we recovered 126 isolates showing affinities to Ceratocystiopsis representing six species, including two described and four undescribed taxa. The four undescribed taxa collected during this work were characterised based on their morphological characteristics and multi-gene phylogenies. Herein, we describe these new species as Ceratocystiopsis chalcographii sp. nov., Ceratocystiopsis debeeria sp. nov., Ceratocystiopsis norroenii sp. nov. and Ceratocystiopsis troendelagii sp. nov. Ceratocystiopsis norroenii and C. rollhanseniana were the most frequently isolated species although the latter species had a much wider vector range. This study expands our knowledge about the taxonomy and species diversity of Ceratocystiopsis and beetle-fungus relationships.