Do Galeate-Ascospore Members of the Cephaloascaceae, Endomycetaceae and Ophiostomataceae Share a Common Phylogeny?

Abstract

Using partial small subunit ribosomal gene sequences we show that yeast-like genera that produce galeate (hat-shaped) ascospores and similar-spored members of the Ophiostomatales do not form a monophyletic group. Based on distance and parsimony methods Cephaloascus fragrans and Endomyces decipiens failed to form a monophyletic grouping with species of Ceratocystis sensu stricto and Ophiostoma. Instead these yeast species clustered with Saccharomyces cerevisiae, Kluyveromyces lactis, and Torulaspora delbrueckii in >9% of both the distance and parsimony majority-rule consensus trees generated using the statistical method of bootstrapping. Therefore galeate ascospores appear to be an example of convergent evolution in fungi and by itself this trait should not be considered as an indicator of evolutionary relatedness.