Cylindromonium dirinariae sp. nov. (Ascomycota, Hypocreales), a new nectrioid lichenicolous species on Dirinaria applanata in Japan.

A nectrioid fungus forming a pinkish colony with mainly solitary phialides producing ellipsoid, aseptate conidia in mucoid packets was isolated from Dirinaria applanata. Our taxonomic study based on morphology and phylogenetic analysis using ITS rDNA sequences revealed that the isolates represented a member of the genus Cylindromonium. Based on further morphological examination, nucleotide sequence comparison, and phylogenetic analysis based on LSU rDNA, tef1, and rpb2 in addition to the phylogenetic analysis using the ITS rDNA sequences, the fungus from Dirinaria represents a new species, which is described here as Cylindromonium dirinariae sp. nov. Furthermore, inoculation experiments revealed that this species can also produce perithecia when inoculated on the host lichen in laboratory environments. Citation: Ohmaki A, Okane I, Crous PW, Verkley GJM (2023). Cylindromonium dirinariae sp. nov. (Ascomycota, Hypocreales), a new nectrioid lichenicolous species on Dirinaria applanata in Japan. Fungal Systematics and Evolution 11: 1-10. doi: 10.3114/fuse.2023.11.01.

Phylogeny of Discosia and Seimatosporium, and introduction of Adisciso and Immersidiscosia genera nova.

Discosia (teleomorph unknown) and Seimatosporium (teleomorph Discostroma) are saprobic or plant pathogenic, coelomycetous genera of so-called 'pestalotioid fungi' within the Amphisphaeriaceae (Xylariales). They share several morphological features and their generic circumscriptions appear unclear. We investigated the phylogenies of both genera on the basis of SSU, LSU and ITS nrDNA and ß-tubulin gene sequences. Discosia was not monophyletic and was separated into two distinct lineages. Discosia eucalypti deviated from Discosia clade and was transferred to a new genus, Immersidiscosia, characterised by deeply immersed, pycnidioid conidiomata that are intraepidermal to subepidermal in origin, with a conidiomatal beak having periphyses. Subdividing Discosia into 'sections' was not considered phylogenetically significant at least for the three sections investigated (sect. Discosia, Laurina, and Strobilina). We recognised Seimatosporium s.l. as a monophyletic genus. An undescribed species belonging to Discosia with its associated teleomorph was collected on living leaves of Symplocos prunifolia from Yakushima Island, Japan. We have therefore established a new teleomorphic genus, Adisciso, for this new species, A. yakushimense. Discostroma tricellulare (anamorph: Seimatosporium azaleae), previously described from Rhododendron species, was transferred to Adisciso based on morphological and phylogenetic grounds. Adisciso is characterised by relatively small-sized ascomata without stromatic tissue, obclavate to broadly cylindrical asci with biseriate ascospores that have 2 transverse septa, and its Discosia anamorph. Based on these features, it can easily be distinguished from Discostroma, a similar genus within the Amphisphaeriaceae.