A new record of fungus-beetle symbiosis in Scolytodes bark beetles (Scolytinae, Curculionidae, Coleoptera)

The most evolutionarily advanced form of symbiosis between wood-decaying fungi and wood-boring beetles (Coleoptera, Curculionidae: Scolytinae and Platypodinae) is the ambrosial habit, or fungus fanning. Here we present a discovery of a new origin of the ambrosia symbiosis in Scolytodes unipunctatus. Feeding on symbiotic fungi and the spatial organization of the gallery system of S. unipunctatus is typical for ambrosia beetles, but not for phylogenetically related phloeophagous species. S. unipunctatus is associated with the fungal genera Raffaelea, Graphium, and Gondwanamyces; the association of the latter with scolytines is documented here for the first time. The fungi were identified using morphological characters and 18S, 28S and ITS regions of rDNA. We report four undescribed fungus species.