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In an ongoing effort to monograph the genus Lasiosphaeria, it is desirable to obtain estimates of the phylogenetic relationships for five uncommon species, L. coacta, L. munkii, L. punctata, L. sphagnorumand L. stuppea.Three additional species previously placed in Lasiosphaeria, Echinosphaeria canescens, Hilberina caudata and Ruzenia spermoides, also were included in this study as well as three undescribed species. These species were believed to have relations elsewhere based on various ambiguous morphological characters, so an independent dataset from one or more genes was used to resolve their phylogenetic affinities. Sequences from the nuclear ribosomal 28S large subunit (LSU) and β-tubulin genes were generated for these taxa. Maximum likelihood and Bayesian analyses indicated these taxa form a well supported monophyletic group with members of the Helminthosphaeriaceae and therefore, should be transferred out of Lasiosphaeria. Except for Helminthosphaeria gibberosa, Hilberina elegans, Ruzenia spermoides and Synaptospora plumbea,all taxa within this clade possess ascomata with distinct thick-walled setae. Based on a combination of morphological and molecular data, Helminthosphaeria tomaculum, Helminthosphaeria triseptataand Hilberina robustaare described as new and four new combinations are proposed: Helminthosphaeria ludens, Hel. stuppea, Hilberina punctataand H. sphagnorum. Ten new combinations are proposed based on morphological data: Echinosphaeria heterostoma, Helminthosphaeria flavocompta, Hel. gibberosa, Hel. heterotricha, Hilberina breviseta, H. elegans, H. foliicola, H. meznaensis, H. moseri and H. rhynchospora. Lasiosphaeria coactais placed in synonymy with Hel. ludensand the previous transfer of Hilberina munkiiis accepted. Synaptospora plumbeawas found to belong in the family. Illustrations are provided for most Helminthosphaeriaceae taxa seen in this study.

Three species of Cercophorawere found during a survey of the biodiversity of microfungi in northwest Argentina. Cercophora argentinapossesses a unique combination of morphological characters and is described as a new species, while C. costaricensisand C. solarisare reported as new records for Argentina. Other species of Cercophoraknown from this region include C. natalitaand C. coprogena, which is fully illustrated for the first time and determined herein to be a synonym of C. californica. All other species are described and illustrated.

Amplistromais described as a new genus for A. carolinianum, A. diminutisporum, A. guianense, A. hallingii, A. ravum, A. tartareumand A. xylarioides. Species of Amplistromaare distinguished by large stromata of textura intricata with polystichous ascomata and long necks that are either erumpent from the stromatal surface or form bumps or protuberances. The type collection of Ceratostoma sphaerospermumwas examined and found to be synonymous with Wallrothiella congregata. The distribution of W. congregatais expanded by collections from Costa Rica, the eastern United States and Puerto Rico. Wallrothiella congregatahas ascomata that are long-necked and develop individually or are gregarious on the substrate but do not form large stromata. Amplistromaand Wallrothiellaare distinguished by small asci with eight, minute, globose ascospores. An acrodontium-like anamorph occurs in both genera. Phylogenetic analyses of 28S large-subunit rDNA sequences group these taxa in a well supported clade distinct from known orders within the Sordariomycetidae but showing unsupported relationships with the Chaetosphaeriales and the Magnaporthaceae. Family Amplistromataceae is described for this clade and placed within the Sordariomycetidae incertae sedis.

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 Chaetomidiumand distribution of the cephalothecoid peridium within this genus we performed phylogenetic analyses with LSU, β-tubulin and rpb2sequence data. The results of these analyses showed that Chaetomidiumis 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 Chaetomidiumwere distributed in three unrelated clades, suggesting that the morphological similarity among these particular species resulted from convergence instead of ancestry.

Ceratosphaerellais described as a new genus for C. castillensisand C. rhizomorpha. The genus is related to Ophiocerasbut distinguished by ascomata with a basal stroma and shorter, fusiform ascospores. Muraeriatais described for M. collapsaand M. africana, two species that are distinguished by having a vacuolate middle ascomal wall layer. The ascospores resemble those of Ceratosphaerellaand ascospores in both genera are morphologically similar to those of Ceratosphaeria lampadophora. Both new genera are placed in the Magnaporthaceae based on LSU and SSU data. A species previously identified as Ophioceras tenuisporumwas re-examined, found to fit the description of Pseudohalonectria phialidicaand is transferred to Ceratosphaeriabased on LSU data. Lentomitella tropicaand L. pallibrunneaare described for two species that have long-necked ascomata with pale brown, ellipsoid ascospores and large ascal rings. Sequence data from the LSU places them in a clade with hyaline-spored Lentomitella crinigeraand L. cirrhosa.

An interesting wood-inhabiting pyrenomycete was discovered while collecting for the All Taxa Biodiversity Inventory currently being conducted in the Great Smoky Mountains National Park. This species is unique in possessing superficial ascomata with reddish tubercles and ascospores that develop an apical swollen brown cell and a long, basal hyaline cell. Because these ascospore characters fit the traditional morphological circumscription of Cercophora, this species is described as a new species within this genus.

Chaetosphaeriais a common saprobic pyrenomycete genus with simple, homogeneous teleomorphs and complex, diverse anamorphs. As currently circumscribed in the literature, the genus encompasses 30 species distributed in four ‘natural groups’, and includes morphological entities in 11 anamorphic genera. Species frequently have been defined primarily based on characters of the anamorphs resulting in species with almost indistinguishable teleomorphs. This study aimed to assess the value and significance of morphological characters in resolving phylogenetic relationships in Chaetosphaeriaand its allied genera. Phylogenetic relationships of 42 taxa, representing 29 species distributed in Chaetosphaeriaand five related genera, were estimated with partial sequences of the nuclear LSU rDNA and β-tubulin genes. Sequences were analyzed with maximum parsimony, maximum likelihood and Bayesian methods. Phylogenetic analyses of these two genes combined revealed two major lineages. The Chaetosphaerialineage includes 21 species possessing both typical and new sexual and asexual morphologies. The lineage contains a strongly supported monophyletic clade of 13 species and eight paraphyletic taxa; the latter includes C. innumera, the type species of the genus. The second major lineage includes groupings concordant with the morphological circumscriptions of the genera Melanochaeta, Melanopsammella, Striatosphaeria, Zignoëllaand the new genus Tainosphaeria.

The Sordariales is a taxonomically diverse group that has contained from seven to 14 families in recent years. The largest family is the Lasiosphaer-iaceae, which has contained between 33 and 53 genera, depending on the chosen classification. To determine the affinities and taxonomic placement of the Lasiosphaeriaceae and other families in the Sordariales, taxa representing every family in the Sordariales and most of the genera in the Lasiosphaeriaceae were targeted for phylogenetic analysis using partial sequences of the large-subunit (LSU) nrDNA. Based on molecular data, only genera within the families Chaetomiaceae, Lasiosphaeriaceae and Sordariaceae are retained within the redefined Sordariales. The order is a coherent group with morphologies that vary along well-defined lines, including large ascomata with large-celled membraneous or coriaceous walls and ascospores that show variation on a distinctive developmental theme, often with appendages or sheaths. The paraphyletic chaetomiaceous complex and the strongly supported Sordariaceae are nested among taxa traditionally placed in the Lasiosphaeriaceae. Analyses also indicate that 11 genera belong in the paraphyletic lasiosphaeriaceous complex. These taxa share a similar developmental pattern in their ascospore morphology that extends to the Sordariales as a whole. Based on these similarities in morphology, 13 additional genera are retained within the lasiosphaeriaceous complex and more than 35 genera have relationships in the order overall. Based on LSU data, 17 genera that have been assigned to the Lasiosphaeriaceae sensu lato are transferred to other families outside the Sordariales and 22 additional genera with differing morphologies subsequently are transferred out of the order. Two new orders, Coniochaetales and Chaetosphaeriales, are recognized for the families Coniochaetaceae and Chaetosphaeriaceae respectively. The Boliniaceae is accepted in the Boliniales, and the Nitschkiaceae is accepted in the Coronophorales. Annulatascaceae and Cephalothecaceae are placed in Sordariomycetidae inc. sed., and Batistiaceae is placed in the Euascomycetes inc. sed.

Paramphisphaeriais described as a new genus on the basis of the single species, P. costaricensis. It differs from Amphisphaeriaspp. primarily in having bicellular ascospores with a germ slit and in having an ascus apical ring that does not become blue in iodine. It resembles Amphisphaeriain its brown color and lack of constriction at the septum of the ascospore. An anamorph is unknown. It tentatively is placed in the Xylariaceae for reasons discussed. Pachytrype rimosais described as a new species.

AbstractChaetosphaeria cylindrosporaand Rimaconus, a new genus for Lasiosphaeria jamaicensis, are described and illustrated. The ascomata of Chaetosphaeria cylindrosporaare gregarious, globose to broadly ovoid and superficial on the substrate, with robust walls of strong structural integrity. The asci of C. cylindrosporaare clavate and long-stipitate and the ascospores are cylindrical, hyaline, and multiseptate. No anamorph was formed in culture and an associated anamorph was found on only a single specimen. In parsimony analyses of partial sequences of the large subunit nrDNA, placement of C. cylindrosporawithin the genus Chaetosphaeriais well supported with high bootstrap values. Rimaconus jamaicensishas conical, immersed to erumpent, melanized ascomata, cylindrical, short-stipitate asci with a refractive apex and hyaline, cylindrical, multiseptate ascospores that are bent at slightly submedian. No anamorph was formed in culture. Family placement is unclear according to analyses of sequences of the large subunit nrDNA, however, it did not show affinities either to Lasiosphaeria ovinaor other members of the Sordariales sensu stricto. Based on morphological characters it is placed in the Pleurotremataceae.