Chaenothecopsis in a molecular phylogeny based on nuclear rDNA ITS and LSU sequences

Bayesian inference analyses of nuclear LSU rDNA sequences showed Verrucariales and Eurotiales to form the sistergroup of Mycocaliciales. A more detailed analysis of ITS rDNA sequences showed Sphinctrinaceae to be embedded in Mycocaliciaceae. Mycocaliciales contain two major lineages. Intron occurrence and phylogeny was partly congruent with the ITS-based phylogeny. Chaenothecopsis is paraphyletic with respect to Phaeocalicium, Mycocalicium, Sphinctrina and Stenocybe. Some morphological features traditionally used for characterising Chaenothecopsis and other genera in Mycocaliciales, such as ascus apex structure and stalk anatomy, were found to be homoplasious, while others, such as spore septation, intron distribution and nutritional biology, were consistent with major clades in the analysis. Within the two major clades of Mycocaliciales some subclades are strongly supported and well characterized by anatomical, nutritional and intron features.