Victoriomyces antarcticus gen. nov., sp. nov., a distinct evolutionary lineage of the Cephalothecaceae (Ascomycota) based on sequence-based phylogeny and morphology

Abstract

In this study, we propose a new genus, Victoriomyces, with a new species, Victoriomyces antarcticus, isolated from soil samples collected in Victoria Land, Antarctica. To determine its taxonomic status and evolutionary relationships, phylogenetic analysis was performed on DNA sequences from the nuclear 18S rRNA, 28S rRNA and the second largest subunit of RNA polymerase II (RPB2) genes. Victoriomyces antarcticus constitutes one well-supported distinct lineage within the Cephalothecaceae (family incertae sedis in Sordariomycetes), in which the only recognised asexual morphs belong to the genus Phialemonium and to Acremonium thermophilum. Victoriomyces antarcticus can be clearly distinguished from these taxa by means of DNA sequence analysis and its morphological traits that consist in having a Metarhizium-like asexual morph, dark red-coloured disk-like structures, immature bodies and the production of an intense red pigment in the growth media. Finally, we inferred the divergence time of V. antarcticus and the Cephalothecaceae using Bayesian analysis and secondary calibration. The holotype of V. antarcticus is FBL 165. The ex-type strain has been deposited as MUT 3686 T and CCF 6158 T. An additional strain of the species is FBL 577. The MycoBank number is MB 823713 for the genus and MB 823714 for the species.

Scaptona ramosa gen. nov., sp. nov., isolated from nest of the stingless bee

“…Its species are pathogens and can infect immunocompromised hosts [37]. The most recent genus is Victoriomyces , characterized by presenting micromorphology similar to Metarhizium ( Hypocreales , Clavicipitaceae ), of dark red disc-like structures, immature bodies and production of an intense red pigment in pure growth [8].…”

“…A notable challenge in identifying taxa within the Cephalotecaceae and related families stems from the limited availability of sequences for protein-coding gene regions. Based on our searches, in the Cephalothecaceae , only the study conducted by Davolos et al [8] performed phylogenetic analyses with the RPB2 and sequencing of the β-tubulin; however, it is noteworthy that the gene for beta tubulin was not employed in the phylogenetic elucidation of Victoriomyces and other related taxa. In this study, we were able to amplify the genes benA and TEF1a .…”

“…The blast n search showed that our strain has similarity to species in Cephalotecaceae . Based on this information, related sequences of the four marker loci, which include representatives belonging to Cephalotecaceae (18 strains), Coniochaetaceae (four strains), Chaetosphaeriaceae (three strains), Cordanaceae (three strains), Boliniaceae (one strain), Sordariaceae (one strain), Gnomoniaceae (one strain) and Ophiostomataceae (one strain), were downloaded according to a recent study [8]. Xylaria hypoxylon AFTOL-ID 51 was selected as the outgroup taxon.…”

“…Currently, Cephalothecales includes only Cephalothecaceae, with five genera, Albertiniella Kirschst., Cephalotheca Fuckel, Cryptendoxyla Malloch and Cain, Phialemonium W. Gams and McGinnis and Victoriomyces Maggi, Davolos and Persiani. Only two genera have asexual morphs described: Phialemonium and Victoriomyces [7,8].…”

Diversity and Seasonal Dynamics of Airborne Fungi in Nerja Cave, Spain

“…Of the 18 species identified in the two seasonal air samples outside the cave, only 8 were not found inside, Tremateia chromolaenae, Victoriomyces antarcticus, Microascus croci, Hyphodermella rosae, Purpureocillium lilacinum, Monocillium indicum, Aspergillus tubingensis, and Aspergillus melleus. Hyphodermella rosae is a white-rot corticioid fungus previously isolated from La Garma Cave air [18], Purpureocillium lilacinum is an entomopathogenic fungus often isolated from caves [50,52,62,64], Monocillium indicum and Victoriomyces antarcticus were found in soils [84,85], Tremateia chromolaenae was associated with plants [86], and Microascus croci with aquatic sediments [87]. The remaining two Aspergillus spp.…”