Leptographium guttulatum sp nov., a new species from spruce and pine in Europe

Leptographium spp. are anamorphs of Ophiostoma and are characterised by conidiophores with dark mononematous stipes and complex conidiogenous apparatusses with several series of branches. These fungi are also characterised by their distinct tolerance to high concentrations of cycloheximide. Most Leptographium spp. cause sapstain in conifer timber and some species are root pathogens of trees. In recent years, an unknown Leptographium sp, has been isolated from spruce and pine in Europe. This species is found in association with bark beetles that infest these conifers. These insects most probably act as vectors for this fungus and belong to the genera Dryocoetes, Hylastes, Hylurgops and Tomicus. Morphological comparisons, as well as partial ribosomal DNA comparisons have shown that this species represents a previously undescribed taxon. In this paper we describe the fungus as new and provide the name Leptographium guttulatum sp. nov. for it.