Notes: Grosmannia was originally erected by Goidànich (1935) to accommodate sexual species of Ceratostomella with leptographium-like asexual morphs (Davidson 1942). The genus was later treated as synonym of both Ophiostoma (Siemaszko 1939) and Ceratocystis (Bakshi 1951). Zipfel et al. (2006) showed that Ophiostoma and Grosmannia were distinct from each other based on ITS and LSU sequences, and separated the two genera based on these and morphological differences. However, the focus of the Zipfel et al. (2006) study was primarily on sexually reproducing species.
De Beer & Wingfield (2013) included sequence data for many more asexual Leptographium spp. in their study and showed that Leptographium and Grosmannia spp. grouped together, along with other previously unassociated Ophiostoma spp. They applied the older name, Leptographium to this group, rather than Grosmannia, which following the dual nomenclature system (McNeill et al. 2012) had preference because it was considered a sexual genus (De Beer & Wingfield 2013). They referred to the lineage as Leptographium s.l., even though the lineage did not show strong monophyletic support. The type species of Grosmannia (G. penicillata) grouped in a lineage distinct from the type species of Leptographium (L. lundbergii). However, they recommended that novel species grouping in what they referred to as the G. penicillata complex should be treated as Grosmannia species. This was until more robust analyses could confirm whether the G. penicillata complex should be treated as a distinct genus.
Based on the data emerging from the present study, we have reinstated Grosmannia as a genus distinct from Leptographium, for species that produce leptographium-like asexual morphs and have allantoid, hyaline and aseptate ascospores. These species are commonly associated with conifer-infesting bark beetles in the Northern Hemisphere (Jacobs & Wingfield 2001, Linnakoski et al. 2012). Based on our phylogenetic analyses, Grosmannia includes the fungus previously known as G. penicillata s.s. (referred to here as the G. penicillata complex), G. abieticola and L. taigense (Lineage C), and the newly recognised G. grandifoliae complex (Jankowiak et al. 2017).

Abstract: The Ophiostomatales was erected in 1980. Since that time, several of the genera have been redefined and others have been described. There are currently 14 accepted genera in the Order. They include species that are the causal agents of plant and human diseases and common associates of insects such as bark beetles. Well known examples include the Dutch elm disease fungi and the causal agents of sporotrichosis in humans and animals. The taxonomy of the Ophiostomatales was confused for many years, mainly due to the convergent evolution of morphological characters used to delimit unrelated fungal taxa. The emergence of DNA-based methods has resolved much of this confusion. However, the delineation of some genera and the placement of various species and smaller lineages remains inconclusive. In this study we reconsidered the generic boundaries within the Ophiostomatales. A phylogenomic framework constructed from genome-wide sequence data for 31 species representing the major genera in the Order was used as a guide to delineate genera. This framework also informed our choice of the best markers from the currently most commonly used gene regions for taxonomic studies of these fungi. DNA was amplified and sequenced for more than 200 species, representing all lineages in the Order. We constructed phylogenetic trees based on the different gene regions and assembled a concatenated data set utilising a suite of phylogenetic analyses. The results supported and confirmed the delineation of nine of the 14 currently accepted genera, i.e. Aureovirgo, Ceratocystiopsis, Esteya, Fragosphaeria, Graphilbum, Hawksworthiomyces, Ophiostoma, Raffaelea and Sporothrix. The two most recently described genera, Chrysosphaeria and Intubia, were not included in the multi-locus analyses. This was due to their high sequence divergence, which was shown to result in ambiguous taxonomic placement, even though the results of phylogenomic analysis supported their inclusion in the Ophiostomatales. In addition to the currently accepted genera in the Ophiostomatales, well-supported lineages emerged that were distinct from those genera. These are described as novel genera. Two lineages included the type species of Grosmannia and Dryadomyces and these genera are thus reinstated and their circumscriptions redefined. The descriptions of all genera in the Ophiostomatales were standardised and refined where this was required and 39 new combinations have been provided for species in the newly emerging genera and one new combination has been provided for Sporothrix. The placement of Afroraffaelea could not be confirmed using the available data and the genus has been treated as incertae sedis in the Ophiostomatales. Paleoambrosia was not included in this study, due to the absence of living material available for this monotypic fossil genus. Overall, this study has provided the most comprehensive and robust phylogenies currently possible for the Ophiostomatales. It has also clarified several unresolved One Fungus-One Name nomenclatural issues relevant to the Order.