RESUMEN
Megacoelomyces (type species: Megacoelomyces sanchezii), an ascomycete asexual morph infecting Myrcia fenzliana (Myrtaceae) from the Brazilian Cerrado, is described as a new genus in the Phaeosphaeriaceae (Pleosporales, Dothideomycetes, Ascomycota), based on multilocus phylogeny (three nuclear ribosomal DNA and two protein-coding genes) in addition to morphological (light and scanning electron microscopy) and ecological data.
Asunto(s)
Clasificación , Hongos Mitospóricos , Ascomicetos/clasificación , Ascomicetos/citología , Ascomicetos/genética , Ascomicetos/ultraestructura , Brasil , ADN de Hongos/genética , ADN Ribosómico/genética , Genes Fúngicos , Microscopía Electrónica de Rastreo , Hongos Mitospóricos/clasificación , Hongos Mitospóricos/citología , Hongos Mitospóricos/genética , Hongos Mitospóricos/ultraestructura , Myrtaceae/microbiología , FilogeniaRESUMEN
Cladosterigma clavariellum has been treated as a basidiomycete since its first description by Spegazzini in 1886 as Microcera clavariella. After further morphological studies, between 1919 and 2011, it remained among the basidiomycetes, most recently as incertae sedis in the order Cryptobasidiales. Our studies, based on light and scanning electron microscopy, supported by multilocus phylogenetic analyses-second-largest subunit of RNA polymerase II (RPB2), translation elongation factor 1-alpha (TEF1), small subunit (18S), large subunit (28S), and nuclear internal transcribed spacers (ITS1-5.8S-ITS2 = ITS) of the nuclear rDNA sequences, and mitochondrial rDNA small subunit (mtSSU)-finally determined the phylogenetic placement of Cladosterigma as the first nonlichenicolous mycoparasitic member of the Gomphillaceae within the Graphidales, an ascomycete order previously composed predominantly of lichen-forming fungi.
Asunto(s)
Ascomicetos/clasificación , Ascomicetos/fisiología , Ascomicetos/citología , Ascomicetos/genética , Brasil , ADN de Hongos/genética , ADN Mitocondrial/genética , ADN Ribosómico/genética , Eugenia/microbiología , Factor 1 de Elongación Peptídica/genética , Filogenia , Hojas de la Planta/microbiología , ARN Polimerasa II/genética , Análisis de Secuencia de ADN , Especificidad de la EspecieRESUMEN
Species of Phaeochorella are biotrophic leaf parasites with a tropical distribution, traditionally accepted in the family Phyllachoraceae, Phyllachorales in classifications based on morphological characters. Phylogenetic evidence presented here resolves the relationship of Phaeochorella within the Sordariomycetes, based on a multilocus analysis of partial nuc rDNA large subunit (28S) and internal transcribed spacers (ITS1-5.8S-ITS2 = ITS), the DNA-directed RNA polymerase II second largest subunit (RPB2), and the translation elongation factor 1-α (TEF1-α) gene. Phylogenetic analyses indicate that Phaeochorella belongs to the Diaporthales rather than the Phyllachorales. Phaeochorella parinarii, the type species of the genus, present on native hosts from the Brazilian Cerrado, forms a unique clade with a species of Phaeoappendicospora with high support. Thus, a new family, Phaeochorellaceae, Diaporthales, including both genera, is herein proposed. With the exception of P. parinarii and P. zonata, all other species in Phaeochorella (P. artocarpi, P. ciliata, P. machaerii) were excluded from the genus.
Asunto(s)
Phyllachorales/clasificación , Phyllachorales/aislamiento & purificación , Filogenia , Ascomicetos/clasificación , Ascomicetos/genética , Ascomicetos/aislamiento & purificación , Brasil , ADN de Hongos/genética , Phyllachorales/genética , ARN Ribosómico 28S/genética , ARN Ribosómico 5.8S/genéticaRESUMEN
Apiosphaeria guaranitica, the causal agent of brown crust disease of several bignoniaceous hosts, among them Handroanthus and Tabebuia species, has been traditionally placed in Phyllachoraceae, based exclusively on morphological studies, without supporting molecular evidence. Here, we provide molecular data for the link between sexual and asexual states of the fungus and elucidate the phylogeny of A. guaranitica. The multilocus phylogenetic analyses employed sequences from the 18S subunit (18S), 28S subunit (28S), and nuclear internal transcribed spacers (ITS1-5.8S-ITS2 = ITS) of the nuc rDNA, second-largest subunit of RNA polymerase II (RPB2), and translation elongation factor 1-α (TEF1) genetic loci. Estimates of the divergence time of this lineage were supported by fossil calibration (FC) and secondary calibration (SC) strategies. Our results indicate a natural placement of Apiosphaeria within Diaporthaceae (Diaporthales), where it represents an ancient lineage of the crown group of Diaporthaceae, diverging during the late Paleocene at 61.15 (FC) and 60.63 (SC) million years ago. This divergence time estimate within Diaporthales is based on Spataporthe taylori, a diaporthaceous fossil.