During a survey of endophytic fungi from the cactus Tacinga inamoena in a Brazilian tropical dry forest (Caatinga) some undescribed ascomycetous fungi were isolated. These fungi are characterized by superficial and immersed, globose to subglobose, smooth or hairy ascomata, bitunicate asci, and muriformly septate, ellipsoidal ascospores. Multigene phylogenetic analyses using sequences from partial ITS, SSU and LSU nrDNA and the translation elongation factor 1-alpha gene (tef1) demonstrated a monophyletic clade accommodating these endophytic fungi in the class Dothideomycetes, closely related to the order Tubeufiales. Based on morphological features and phylogenetic analyses, these fungi could not be placed in the order Tubeufiales, in the new order Wiesneriomycetales, or any other known genus in the class Dothideomycetes. Thus, two new genera (Bezerromyces, with B. brasiliensis and B. pernambucoensis, and Xiliomyces with X. brasiliensis), a new family (Bezerromycetaceae) and a new order (Bezerromycetales) are introduced to accommodate these novel taxa. Our phylogenetic analyses also demonstrated that the clade accommodating Wiesneriomycetaceae represents a new order, here introduced as Wiesneriomycetales.