Colacosiphon:: a new genus described for a mycoparasitic fungus

An undescribed heterobasidiomycetous fungus was found in cultures originating from bark beetles placed onto a natural medium. Spores were borne apically oil extraordinarily long, filiform, aseptate structures arising from swollen hyphal cells. Within these cells, parasitic interactions with hyphae of an unidentified ascomycete by colacosomes were found. The septal pores of the parasitic fungus were simple and associated with microbodies containing inclusions similar to those of Woronin bodies. The fungus is closely related to Cryptomycocolax abnormis, the single species of the hitherto monotypic order Cryptomycocolacales. The undescribed fungus differs from C. abnormis by the presence of only one type of colacosome, the absence of clamps, and the absence of a transversely septate stage during sporogenesis. A new genus and species is proposed for the undescribed fungus: Colacosiphon filiformis. Since it is not clear whether the unusual sporogenous structures are conidiophores or basidia, the new taxon was preliminarily considered as anamorphic.