Abstract:
Two species of blue-stain fungi with similar morphologies, Ophiostoma brunneociliatum
and O. clavatum, are associates of bark beetles infesting Pinus spp. in Europe. This
has raised questions whether they represent distinct taxa. Absence of herbarium specimens and
contaminated or mistakenly identified cultures of O. brunneo-ciliatum and O. clavatum have
accentuated the uncertainty regarding their correct identification. The aim of this study was to
reconsider the identity of European isolates reported as O. brunneo-ciliatum and O. clavatum
by applying DNA-based identification methods, and to provide appropriate type specimens for
them. Phylogenetic analyses of the ITS, βT, TEF-1 and CAL gene sequences revealed that the
investigated isolates represent a complex of seven cryptic species. The study confirmed that
ITS data is insufficient to delineate species in some Ophiostoma species clusters. Lectotypes and epitypes were designated for O. clavatum and O. brunneo-ciliatum, and three new species,
O. brunneolum, O. macroclavatum and O. pseudocatenulatum, were described in the newly
defined O. clavatum-complex. The other two species included in the complex are O. ainoae
and O. tapionis. The results suggest co-evolution of these fungi in association with specific bark
beetles. The results also confirm the identity of the fungus associated with the pine bark beetle
Ips acuminatus as O. clavatum, while O. brunneo-ciliatum appears to be mainly associated with
another pine bark beetle, Ips sexdentatus.
