Anaeromyces corallioides, sp. nov., a new anaerobic gut fungus from the faeces of cattle

We report on the isolation and characterization of three isolates of anaerobic gut fungi from a cattle faecal sample obtained in Stillwater, OK, USA. The isolates produced polycentric thalli with nucleated rhizomycelia, lobed appressorium-like structures, intercalary sporangia and constricted sausage-like hyphae. These morphological features are characteristic of members of the genus <i>Anaeromyces</i>. No zoospore production was observed during the isolation process or thereafter. The strains seemed to have propagated solely through their nucleated hyphae post initial enrichment. Phylogenetic analysis of the D1/D2 region of the large ribosomal subunit (D1/D2 LSU) rRNA, the ribosomal intergenic spacer region 1 (ITS1), RNA polymerase II large subunit (RPB1) and comparative average amino acid identity using transcriptomic datasets further confirmed the position of the type strain as a distinct member of the genus <i>Anaeromyces</i>, family <i>Anaeromycetaceae</i> and phylum <i>Neocallimastigomycota</i>. We propose to accommodate these isolates into a new species (<i>Anaeromyces corallioides</i>) within the genus <i>Anaeromyces</i>. The type strain is EE.1.