Molecular phylogeny of the cleistothecial fungi placed in Cephalothecaceaeand Pseudeurotiaceae

Ample evidence from both morphological and molecular characters has accumul ated to establish that the cleistothecial ascoma has been derived independe ntly on different occasions from perithecial and apothecial ascomycetes. In order to clarify, the phylogenetic position of additional species of cleis tothecial ascomycetes, particularly those placed in the Cephalothecaceae an d Pseudeurotiaceae of the Eurotiales, partial sequences of the small and la rge subunit ribosomal DNAs of fourteen taxa were compared with those of oth er ascomycetes. Phylogenetic trees from both sequence sets showed that some species in Pseudeurotiaceae are closely related to the taxa of four differ ent orders of the perithecial ascomycetes (Hypocreales, Sordariales, Ophios tomatales, and Xylariales). Others (species of Pleuroascus, Connersia, Leuc oneurospora, and Pseudeurotium) were not closely related to perithecial asc omycetes or Eurotiales, but to discomycetes and loculoascomycetes. Cephalot heca sulfurea, the type of the Cephalothecaceae, formed a monophyletic grou p with pseudeurotiaceous species of Cryptendoxyla and Albertiniella. The ph ylogeny provided in this study suggests strong ly that all of these fungi a re excluded from the Eurotiales where they have been placed and that they d o not form a natural group.