Phacidium and Ceuthospora (Phacidiaceae) are congeneric: taxonomic and nomenclatural implications

Abstract

The morphologically diverse genus Ceuthospora has traditionally been linked to Phacidium sexual morphs via association, though molecular or cultural data to confirm this relationship have been lacking. The aim of this study was thus to resolve the relationship of these two genera by generating nucleotide sequence data for three loci, ITS, LSU and RPB2. Based on these results, Ceuthospora is reduced to synonymy under the older generic name Phacidium. Phacidiaceae (currently Helotiales) is suggested to constitute a separate order, Phacidiales (Leotiomycetes), as sister to Helotiales, which is clearly paraphyletic. Phacidiaceae includes Bulgaria, and consequently the family Bulgariaceae becomes a synonym of Phacidiaceae. Several new combinations are introduced in Phacidium, along with two new species, P. pseudophacidioides, which occurs on Ilex and Chamaespartium in Europe, and Phacidium trichophori, which occurs on Trichophorum cespitosum subsp. germanicum in The Netherlands. The generic name Allantophomopsiella is introduced to accommodate A. pseudotsugae, a pathogen of conifers, while Gremmenia is resurrected to accommodate the snow-blight pathogens of conifers, G. abietis, G. infestans, and G. pini-cembrae.

Resolving Tiarosporella spp. allied to Botryosphaeriaceae and Phacidiaceae

“…belong to the Botryosphaeriaceae. Those species clustering in the Phacidiaceae (see Crous et al 2014), are associated with needle diseases of conifers (Karadžić 1998, Müller & Hantula 1998, and would be better allocated to the genus Darkera, for which a new species, D. picea, occurring on Picea spp. in Finland, Norway and Switzerland is introduced.…”

Towards incorporating asexual fungi in a natural classification: checklist and notes 2012–2016

“…Hernández-Restrepo et al (2016) introduced this hyphomycetous genus and showed that it belongs to Stachybotryaceae. Crous Crous et al (2014b) introduced this coelomycetous genus and showed that it belongs in Phacidiaceae.…”

<p><strong>Resolving <em>Tiarosporella </em>spp. allied to Botryosphaeriaceae and Phacidiaceae</strong></p>

“…Because T. abietis is not congeneric with the genus Tiarosporella, we propose to use the name of the sexual morph, Darkera, for D. abietis and other taxa congeneric with it (Whitney et al 1975). The asexual morph of Darkera resembles species of Phacidium (= Ceuthospora, Crous et al 2014), but the latter tends to have multilocular conidiomata with several semi-papillate ostioles, smaller conidia and branched conidiophores. Species of Darkera are endophytic, and possibly weakly pathogenic on conifers (Müller & Hantula, 1998 Note:--This taxon is known to occur on Abies spp., with conidia being 33-60  9.5-13.5 µm (Karadžić 1998).…”