Phylogenetic circumscription of Arthrographis (Eremomycetaceae, Dothideomycetes)

Abstract

Numerous members of Ascomycota and Basidiomycota produce only poorly differentiated arthroconidial asexual morphs in culture. These arthroconidial fungi are grouped in genera where the asexual-sexual connections and their taxonomic circumscription are poorly known. In the present study we explored the phylogenetic relationships of two of these ascomycetous genera, Arthrographis and Arthropsis. Analysis of D1/D2 sequences of all species of both genera revealed that both are polyphyletic, with species being accommodated in different orders and classes. Because genetic variability was detected among reference strains and fresh isolates resembling the genus Arthrographis, we carried out a detailed phenotypic and phylogenetic analysis based on sequence data of the ITS region, actin and chitin synthase genes. Based on these results, four new species are recognised, namely Arthrographis chlamydospora, A. curvata, A. globosa and A. longispora. Arthrographis chlamydospora is distinguished by its cerebriform colonies, branched conidiophores, cuboid arthroconidia and terminal or intercalary globose to subglobose chlamydospores. Arthrographis curvata produced both sexual and asexual morphs, and is characterised by navicular ascospores and dimorphic conidia, namely cylindrical arthroconidia and curved, cashewnut-shaped conidia formed laterally on vegetative hyphae. Arthrographis globosa produced membranous colonies, but is mainly characterised by doliiform to globose arthroconidia. Arthrographis longispora also produces membranous colonies, but has poorly differentiated conidiophores and long arthroconidia. Morphological variants are described for A. kalrae and our results also revealed that Eremomyces langeronii and A. kalrae, traditionally considered the sexual and asexual morphs of the same species, are not conspecific.

Redefining <I>Microascus, Scopulariopsis</I> and allied genera

“… Valmaseda et al (1986) erected the new monotypic genus Pithoascina for the arthroconidia-forming species P. langeronii. Based on these features, P. langeronii was later transferred to the genus Eremomyces ( Eremomycetaceae , Dothideomycetes ) by Malloch & Sigler (1988) and more recently to Arthrographis , being renamed as Arthrographis arxii ( Giraldo et al 2014 ).…”

Fungal Planet description sheets: 716–784

“…Notes — Pseudoarthrographis is morphologically similar to the genus Arthrographis , which also resides in the Dothideomycetes ( Eremomycetaceae ). Species of Arthrographis have been isolated from the air, compost, marine sediments, soil, wood and also from opportunistic human infections ( Giraldo et al 2014 ). Another genus to consider in this description is Arthropsis , which accommodates species with dark arthroconidia, joined by adjacent connectives and developing from undifferentiated conidiogenous hyphae ( Sigler et al 1982 ).…”

Arthrographis curvata and Rhodosporidium babjevae as New Potential Fungal Lipase Producers for Biotechnological Applications

“…BLAST analysis of the entire ITS region revealed that LE.170 strain had 99% similarity to Arthrographis curvata and to Arthrographis kalrae. The microscopic examination showed curved and cashew-nut-shaped arthroconidia, a feature characterizing A. curvata over A. kalrae [35]. The latter is known to have cylindrical with truncate arthroconidia [35].…”