The PhyloCode applied to Cintractiellales, a new order of smut fungi with unresolved phylogenetic relationships in the Ustilaginomycotina

Abstract

<p>The PhyloCode is used to classify taxa based on their relation to a most recent common ancestor as recovered from a phylogenetic analysis. We examined the first specimen of <i>Cintractiella</i> (<i>Ustilaginomycotina</i>) collected from Australia and determined its systematic relationship to other <i>Fungi</i>. Three ribosomal DNA loci were analysed both with and without constraint to a phylogenomic hypothesis of the <i>Ustilaginomycotina</i>. <i>Cintractiella</i> did not share a most recent common ancestor with other orders of smut fungi. We used the PhyloCode to define the <i>Cintractiellales</i>, a monogeneric order with four species of <i>Cintractiella</i>, including <i>C. scirpodendri sp. nov.</i> on <i>Scirpodendron ghaeri</i>. The <i>Cintractiellales</i> may have shared a most recent common ancestor with the <i>Malasseziomycetes</i>, but are otherwise unresolved at the rank of class.</p>