Pileospora piceae gen. et sp. nov. (Septorioideaceae, Botryosphaeriales) from Picea rubens

During a survey of conifer-associated fungi from the Acadian forest in Eastern Canada, an unidentified endophyte species was isolated from surface-sterilized red spruce (Picea rubens) needles. Conidiomata developed in vitro and produced dimorphic conidia, which provided morphological evidence of its position within Botryosphaeriales. Corresponding conidiomata were also observed on a dead red spruce twig. Phylogenetic analyses using nuc internal transcribed spacer rDNA (ITS) and partial 28S nuc rDNA (LSU) sequences confirmed its relationship within Botryosphaeriales, in a polytomy containing Saccharataceae and Septorioideaceae. Based on morphological and phylogenetic evidence, we describe a novel monotypic genus and species as Pileospora piceae, tentatively placed within Septorioideaceae. ITS similarity shows P. piceae was previously detected in an unrelated study as an unidentified fungal endophyte of black spruce (Picea mariana) from Eastern Quebec.