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Based on a number of isolates of Myceliophthora (Chaetomiaceae, Sordariales, Ascomycota) recently isolated from soil samples collected in USA, the taxonomy of the genus was re-evaluated through phylogenetic analyses of sequences from the nuc rDNA internal transcribed spacer region and genes for the second largest subunit of RNA polymerase II and translation elongation factor 1α. Members of Myceliophthora were split into four monophyletic clades strongly supported by molecular and phenotypic data. Such clades correspond with Myceliophthora, now restricted only to the type species of the genus Corynascus, which is re-established with five species, the new monotypic genus Crassicarpon and also the new genus Thermothelomyces (comprising four species). Myceliophthora lutea is mesophilic and a permanently asexual morph compared to the members of the other three mentioned genera, which also are able to sexually reproduce morphs with experimentally proven links to their asexual morphs. The asexual morph of M. lutea is characterized by broadly ellipsoidal, smooth-walled conidia with a wide, truncate base. Crassicarpon thermophilum is thermophilic and heterothallic and produces spherical to cuneiform, smooth-walled conidia and cleistothecial ascomata of smooth-walled, angular cells and ascospores with a germ pore at each end. Corynascus spp. are homothallic and mesophilic and produce spherical, mostly ornamented conidia and cleistothecial ascomata with textura epidermoidea composed of ornamented wall cells, and ascospores with one germ pore at each end. Thermothelomyces spp. are thermophilic, heterothallic and characterized by similar ascomata and conidia as Corynascus spp., but its ascospores exhibit only a single germ pore. A dichotomous key to distinguish Myceliophthora from the other mentioned genera are provided, as well as dichotomous keys to identify the species of Corynascus and Thermothelomyces. A new species, namely Corynascus fumimontanus, characterized by verrucose ascomatal wall cells and irregularly shaped ascospores, is described and illustrated., (© 2015 by The Mycological Society of America.)

Genus Hamigera was erected for Talaro-myces species that make asci singly instead of in chains. Initially it contained two species, H. avellanea and H. striata. We describe six new species in the genus, H. fusca, H. inflata, H. insecticola, H. pallida, H. paravellanea and H. terricola. Merimbla ingelheimensis is a distinct anamorphic species in the Hamigera clade. None of our DNA sequence data (BT2, calmodulin, ITS, 1su rDNA, RPB2, Tsr1 and Mcm7) supported the placement of H. striata in the same clade as H. avellanea, thus we accepted Talaromyces striatus. In addition to Hamigera species we examined the phylogenetic disposition of Warcupiella spinulosa, Penicillium megasporum, Penicillium arenicola and Merimbla humicoloides. Despite nominal similarity of some of these species to Merimbla, none of these species are part of the Hamigera clade and M. humicoloides is placed in Penicillium to have a monophyletic genus Hamigera.

Chaetomidium, a genus in the Chaetomiaceae, comprises 12 species that produce similar cleistothecial ascomata with a membranous, mostly pilose, peridium. Approximately six species of this genus produce some type of modified peridium composed of cephalothecoid plates that previous authors have hypothesized to be a homologous character within the genus. To better understand the phylogenetic affiliations of Chaetomidium and distribution of the cephalothecoid peridium within this genus we performed phylogenetic analyses with LSU, beta-tubulin and rpb2 sequence data. The results of these analyses showed that Chaetomidium is polyphyletic and should be restricted to its type, C. fimeti, and C. subfimeti. The remaining cephalothecoid and non-cephalothecoid species were scattered throughout the Chaetomiaceae and Lasiosphaeriaceae. The cephalothecoid species of Chaetomidium were distributed in three unrelated clades, suggesting that the morphological similarity amo'ng these particular species resulted from convergence instead of ancestry.

Two new ascomycetes, Boerlagiomyces costaricensis (Pleosporales) and Scopinella musciformis (Sordariales sensu lato), from litter samples collected in rainforests of Costa Rica, are described and illustrated. Boerlagiomyces costaricensis has globose, ostiolate ascomata covered by numerous setae-like hairs; cylindrical, fissitunicate asci without apical structures; and large, fusiform, muriform, hyaline to pale brown ascospores. Scopinella musciformis is characterized by ostiolate ascomata with a few compact clusters of hypha-like hairs distributed on the peridial surface and a long neck; ovate to ellipsoidal unitunicate asci; and small quadrangular ascospores with diagonal germ slits.

Two new species of ascomycetes, Apiosordaria antarctica, isolated from soil, and Thielavia antarctica, isolated from a sample of the lichen Usnea cf. aurantio-atra, both collected on King George Island (Antarctica), are described and illustrated. Apiosordaria antarctica is characterized by ostiolate ascomata with agglutinated hairs, eight-spored, uniseriate and cylindrical asci, and two-celled, irregularly navicular ascospores, with an upper cell ornamented with very small warts and with an apical germ pore. Thielavia antarctica is characterized by nonostiolate ascomata, with a thick peridium, eight-spored, cylindrical asci, uniseriate, oblate, ovoid ascospores, a slightly protruding apical germ pore, and a phialidic anamorph.

Poroconiochaeta tetraspora sp. nov., isolated from soil of Russia, is described and illustrated. The new taxon differs from P. discoidea in its four-spored asci (eight-spored in P. discoidea) and from P. punctulata in the pattern of ascospore ornamentation, which is conspicuously pitted in P. tetraspora (punctulate in the other species). The new combination Poroconiochaeta savoryi is proposed and discussed.

Apiosordaria hispanica sp. nov. and Apiosordaria globosa sp. nov. isolated from soil samples collected in Tarragona, Catalonia, Spain, are described and illustrated. Both species are morphologically close to A. otanii. The ascospores of A. hispanica have tuberculate walls, while those of A. otanii have small warts. Apiosordaria globosa differs from those species by the globose upper cell of the ascospores, which has a small apical protrusion with sub-apical germ pore when young. In A. hispanica and A. globosa the lower cells of the ascospores are slightly warted, while in A. otanii the lower cell of the ascospores is smooth-walled.

Two new conidial fungi, Dictyochaetopsis brasiliensis and Paraceratocladium bacilliformis, both isolated from plant debris collected in Brazil, are described and illustrated. Dictyochaetopsis brasiliensis differs from the previously described species of the genus mainly by small, fusiform conidia with a very thin apical setula, absence of setae, and lateral, discrete conidiogenous cells with usually numerous sympodial proliferations. Paraceratocladium bacilliformis is characterized by small, bacilliform and aseptate conidia.

Syspastospora tropicalis sp. nov. isolated from soil samples from different tropical regions is described and illustrated. The fungus can be easily separated from the other species of the genus by its setose perithecial ascomata with a short papillate neck.

Podospora selenospora sp. nov. isolated from soil in Chile is described and illustrated. It belongs to the group of Podospora species with cylindrical asci, and inequilateral or curved ascospores, with a small, quickly evanescent primary appendage and absence of secondary appendages.