RESUMO
Two new species of Viannaia from the intestine of the North American opossums, Didelphis virginiana (Virginia opossum), and Philander opossum (gray four-eyed opossum), are described based on morphological and molecular data, through an integrative taxonomic approach. Maximum likelihood and Bayesian inference analyses for each dataset and the concatenated dataset were performed using a mitochondrial cytochrome c oxidase subunit 1 (COI) gene, and the nuclear ribosomal internal transcribed spacer region (ITS1-5.8S-ITS2). The phylogenetic analyses revealed 2 new species that occur in Mexico, one from the western state of Colima and another from the southern state of Chiapas. Our phylogenetic trees for both molecular markers and concatenated datasets yielded similar topologies with high bootstrap values and posterior probabilities. Viannaia is recovered as a monophyletic group, but the family Viannaiidae appears as non-monophyletic, due to the position of Travassostrongylus scheibelorum, similar to previous studies. Finally, the morphology of Viannaia and Hoineffia is discussed.
Assuntos
Gambás/parasitologia , Trichostrongyloidea/classificação , Tricostrongiloidíase/veterinária , Animais , Teorema de Bayes , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , DNA Intergênico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Genes Mitocondriais , Intestinos/parasitologia , Funções Verossimilhança , Masculino , México/epidemiologia , Filogenia , RNA Ribossômico 5,8S/genética , Alinhamento de Sequência , Trichostrongyloidea/anatomia & histologia , Trichostrongyloidea/genética , Trichostrongyloidea/ultraestrutura , Tricostrongiloidíase/epidemiologia , Tricostrongiloidíase/parasitologiaRESUMO
Species of Russula are ubiquitous members of ectomycorrhizal fungal communities in tropical ecosystems. However, an important part of the total tropical diversity of this genus and its biogeographic patterns is unknown due to the lack of studies on Russula in tropical ecosystems. We combined molecular, morphological, ecological, and biogeographic data to elaborate concepts for two new subspecies of R. floriformis (subsection Substriatinae). Russula floriformis subsp. floriformis and R. floriformis subsp. symphoniae are described as new from montane forest dominated by Quercus and/or Oreomunnea (Fagales) from Colombia and Panama, respectively. Phylogenies were constructed using nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS), D1-D2 domains of nuc 28S rDNA (28S), and partial regions of the second largest subunit of RNA polymerase II (rpb2) and translation elongation factor 1-alpha (tef1). Similar environmental conditions, similar morphology, and an ITS sequence similarity higher than 99% with only three different positions indicate that these two subspecies are closely related. Detailed observations of microscopic structures and analyses of further DNA loci, however, revealed morphological and molecular characteristics that allow distinguishing the two subspecies of R. floriformis. Spatial distribution and phylogenetic proximity of the two Russula subspecies and their ectomycorrhizal hosts, i.e., species of Quercus, suggest that their diversification is a result of comigration, adaptation, and geographic isolation along the Isthmus of Panama during the Pliocene and Pleistocene.
Assuntos
Ecossistema , Análise por Conglomerados , DNA Fúngico/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Filogenia , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S , Análise de Sequência de DNARESUMO
The genus Bannoa consists of four described species associated with dead leaves in southwestern Japan. In this study, we describe three new species, Bannoa guamensis, B. rosea, and B. tropicalis, from the South Pacific island of Guam and Guyana in South America. Isolates were obtained from surfaces of diseased and healthy leaves of plants in the Euphorbiaceae, Asteraceae, and Poaceae. DNA sequences from four gene regions, including nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 (ITS), D1-D2 domains of nuc 28S rDNA (28S), nuc 18S rDNA (18S), and a portion of tef1, which encodes translation elongation factor 1-alpha, were produced for phylogenetic analysis. Intercompatibility tests were performed, and subsequent development of clamp connections and basidia were documented for B. tropicalis. Potential life history strategies and association with diseased leaves, including rust-infected leaves, were evaluated across the genus. This is the first report of a species of Bannoa from South America.
Assuntos
Basidiomycota/classificação , Filogenia , Folhas de Planta/microbiologia , Clima Tropical , Basidiomycota/isolamento & purificação , DNA Espaçador Ribossômico/genética , Guiana , Hifas , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNARESUMO
To meet a global demand for timber, tree plantations were established in South America during the first half of the 20th century. Extensive plantings of non-native species now are found in Brazil, Chile, Argentina, and Uruguay. In Colombia, miscellaneous plantations were established in the 1950s, during a period of intensive local logging, when policies to limit deforestation in native Quercus humboldtii forests were established. One unforeseen consequence of planting non-native trees was the simultaneous introduction and subsequent persistence of ectomycorrhizal fungi. We sought to document the origins and spread of the introduced Amanita muscaria found in Colombian plantations of the Mexican species Pinus patula, North American species P. taeda, and Australian species Acacia melanoxylon and Eucalyptus globulus. In Colombia, Amanita muscaria is establishing a novel association with native Q. humboldtii and has spread to local Q. humboldtii forests. According to a Bayesian phylogeny and haplotype analysis based on the nuclear rDNA internal transcribed spacer region ITS1-5.8-ITS2 (ITS barcode), A. muscaria individuals found in four exotic plant species, and those colonizing Q. humboldtii roots, have a Eurasian origin and belong to two Eurasian haplotypes. This is the first time the spread of an introduced mutualist fungus into native Colombian Q. humboldtii forests is reported. To arrest its spread, we suggest the use of local inocula made up of native fungi, instead of inocula of introduced fungi.
Assuntos
Amanita/crescimento & desenvolvimento , Amanita/isolamento & purificação , Especificidade de Hospedeiro , Quercus/microbiologia , Acacia/microbiologia , Amanita/genética , Análise por Conglomerados , Colômbia , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Eucalyptus/microbiologia , Florestas , Filogenia , Pinus/microbiologia , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNARESUMO
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.
Assuntos
Phyllachorales/classificação , Phyllachorales/isolamento & purificação , Filogenia , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Brasil , DNA Fúngico/genética , Phyllachorales/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genéticaRESUMO
Seven species of bioluminescent fungi are recorded from the cloud forests in Mexico. Six represent new species belonging to the genus Mycena, whereas Mycena globulispora is a new distribution record for the country. Descriptions, illustrations, photographs, and an identification key to bioluminescent fungi species from Mexico are provided. Sequences of nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) region were generated for barcoding purposes and comparisons with similar species.
Assuntos
Agaricales/classificação , Agaricales/isolamento & purificação , Luminescência , Filogenia , Agaricales/genética , Agaricales/fisiologia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , México , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNARESUMO
Aquanectria and Gliocladiopsis are two closely related genera of Hypocreales. They are also morphologically similar, forming hyaline, penicillate conidiophores and hyaline, straight to sinuous, 0-1-septate phialoconidia. During a revision of gliocladiopsis-like isolates originating from rain forest areas of South America (Ecuador, French Guiana) and Southeast Asia (Singapore), multilocus phylogenetic inferences, based on DNA sequences encoding partial ß-tubulin (TUB2), translation elongation factor 1-α (TEF1- α), histone H3 (HIS3) genes and the nuc rDNA internal transcribed spacer region (ITS1-5.8S-ITS2 = ITS), revealed the occurrence of seven new phylogenetic species. These phylogenetic species also revealed unique combinations of phenotypes, allowing morphological distinction from their closest phylogenetic relatives. Four new species of Aquanectria and three new species of Gliocladiopsis are described and illustrated. Three of the four Aquanectria species deviate from the other species in the genus by having shorter conidia, which are in the size range observed in Gliocladiopsis species. They are placed in Aquanectria based on the phylogenetic analysis, but this also makes the morphological distinction between these two genera obsolete.
Assuntos
Hypocreales/classificação , Hypocreales/isolamento & purificação , Filogenia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Equador , Microbiologia Ambiental , Guiana Francesa , Histonas/genética , Hypocreales/genética , Hypocreales/crescimento & desenvolvimento , Microscopia , Fator 1 de Elongação de Peptídeos/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Singapura , Tubulina (Proteína)/genéticaRESUMO
BACKGROUND: Twelve species of Filisoma Van Cleave, 1928 are recognized parasitizing tropical and subtropical fish. Four of these species were described from kyphosid fish and it has been suggested that a co-speciation may have occurred among species of Kyphosus Lacepède, 1801 and Filisoma, which could provide valuable information about the evolution history of this host-parasite system. PURPOSE: During a survey of the helminth fauna of Kyphosus sectatrix (Linnaeus, 1758) and Kyphosus incisor (Cuvier, 1831) (Kyphosidae Jordan, 1887) off Rio de Janeiro coast, a new species of Filisoma was found and is described herein based on morphological, genetic, and ultrastructural data. METHODS: Fish were obtained off Rio de Janeiro coast, Brazil. The parasites found in the intestine were measured and drawings were made with a drawing tube. Type specimens were deposited at the Helminthological Collection of Oswaldo Cruz Institute (CHIOC). The ultrastructure was studied using scanning electron microscope. The genetic analysis included the study of the partial sequences of 18S, ITS1, 5.8S and 28S rDNA, and the mitochondrial cytochrome c oxidase 1 gene (cox 1), with phylogenetic reconstructions based on the maximum likelihood analysis. RESULTS: Filisoma caudata n. sp. is characterized by a proboscis with 16â18 longitudinal rows of 38â45 hooks each. Hooks are uniform in shape dorsoventrally, gradually decreasing in size towards the base of the proboscis. Anterior hooks are 30â45 µ long, middle hooks 30â35 µ long and 5 basal transversal hooks 20â30 µ long. The new species is differentiated from the closest species Filisoma filiformis Weaver and Smales, 2013 by the size and distribution of hooks, apart from having a subterminal vulva and a curved posterior trunk end (tail) measuring 500â1,000 long. Phylogenetic analysis based on 18S, 28S rDNA and mtDNA-cox1 markers grouped the new species with Filisoma bucerium Van Cleave, 1940 and Filisoma rizalinum Tubangui and Masiluñgan, 1946 showing a close relationship between these species of Cavisomidae Meyer, 1932 and Echinorhynchidae Cobbold, 1879; the latter represented by species of Acanthocephalus Koelreuther, 1771. The new species can be differentiated from others on morphological and molecular basis. A key to the 13 species of Filisoma Van Cleave, 1928 is provided. CONCLUSION: Filisoma caudata n. sp. is described herein based on morphological, genetic, and ultrastructural data. The topologies of obtained phylogenies suggest that species of Echinorhynchidae should be reevaluated since the family is considered paraphyletic in all analyses conducted.
Assuntos
Acantocéfalos/classificação , Acantocéfalos/isolamento & purificação , Doenças dos Peixes/parasitologia , Helmintíase Animal/parasitologia , Perciformes/parasitologia , Acantocéfalos/anatomia & histologia , Acantocéfalos/genética , Animais , Brasil , Análise por Conglomerados , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Estudos Longitudinais , Microscopia , Microscopia Eletrônica de Varredura , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNARESUMO
Adults of the genus Austrodiplostomum are parasites in cormorants of the New World, whereas metacercariae are parasites from eye globe and brain of freshwater and brackish water fishes. In this study, specimens of Austrodiplostomum mordax from South America (type-species) were analyzed together with other specimens of Austrodiplostomum spp. collected from several locations across Middle America and North America. Partial DNA sequences of the mitochondrial gene cytochrome c oxidase subunit I ( COI), the internal transcribed spacers ( ITS1, ITS2, and 5.8S gene), and the D2-D3, domains of the large subunit ( LSU) of nuclear ribosomal DNA, were generated for both developmental stages and compared with available sequences of Austrodiplostomum spp. Phylogenetic analyses inferred with each molecular marker using maximum likelihood and Bayesian inference revealed the existence of 4 lineages representing 2 described species, A. mordax and Austrodiplostomum compactum (syn. Austrodiplostomum ostrowskiae) and 2 undescribed species of Austrodiplostomum recognized in previous studies. The COI haplotype network inferred with 172 sequences detected 28 haplotypes divided into 4 clusters, separating each other by 33 and 40 substitutions and with a genetic divergence ranging from 9 to 12%. The largest group included specimens identified as A. compactum plus those identified as A. ostrowskiae, supporting the synonymy of both species. As a result, we conclude that A. compactum is widely distributed across the Americas, in locations of the United States, Mexico, El Salvador, Honduras, Costa Rica, Venezuela, Peru, and Brazil. The other 2 undescribed species of the genus Austrodiplostomum were previously recorded in the United States and now are reported in Mexico. These 2 species cannot be described because adult forms have not been found in their definitive hosts. Finally, the species A. mordax has been found only in some lakes from Argentina, and it was validated in this study through molecular analyses.
Assuntos
Doenças das Aves/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Doenças dos Peixes/parasitologia , Genes Mitocondriais/genética , Trematódeos/classificação , Animais , Sequência de Bases , Teorema de Bayes , Aves , Encéfalo/parasitologia , América Central , DNA Intergênico/química , DNA Ribossômico/química , Peixes , Água Doce , Haplótipos , Funções Verossimilhança , Metacercárias/classificação , Metacercárias/genética , América do Norte , Filogenia , RNA Ribossômico 5,8S/genética , Águas Salinas , América do Sul , Trematódeos/genética , Corpo Vítreo/parasitologiaRESUMO
This work reports important results of aromatic profiles produced by native yeasts isolated from desert-grown wine grapes from the south of Chihuahua, México. These grapes stand very high temperatures during the ripening season, developing high sugar concentration and high pH. Yeast species found in grapes were identified by polymerase chain reaction and sequence analysis of the 5.8S internal transcribed spacer ribosomal RNA region. Aureobasidium namibiae, Sporobolomyces johnsonii, Candida apicola, Hanseniaspora uvarum, Candida thaimueangensis, Hanseniaspora opuntiae were identified. All of them can grow at glucose concentration of 35% (w/v) and 100 ppm of SO2, and produce low volatile acidity (0.2-1.0 g acetic acid/L). Volatile organic compounds analysis showed that C. thaimueangensis and one strain of C. apicola produce high levels of esters, and Hanseniaspora species produces high levels of higher alcohols and carbonyl compounds. The results of this study contribute to the knowledge about yeast communities associated with desert-grown winegrape yeasts.
Assuntos
Fermentação , Vitis/microbiologia , Leveduras/classificação , Leveduras/metabolismo , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Glucose/metabolismo , México , Filogenia , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Compostos Orgânicos Voláteis/metabolismo , Leveduras/genética , Leveduras/isolamento & purificaçãoRESUMO
BACKGROUND: Sporotrichosis is a subcutaneous mycosis that affects humans and other animals. Infection prevails in tropical and subtropical countries. Until a few years ago, it was considered that two varieties of Sporothrix schenckii caused this mycosis, but by applying molecular taxonomic markers, it has been demonstrated that there are several cryptic species within S. schenckii complex which varies in susceptibility, virulence, and geographic distribution. OBJECTIVE: This study aimed to identify the clinical isolates of Sporothrix spp. from patients with sporotrichosis in Medellin, Colombia, using two markers and to evaluate the in vitro susceptibility to itraconazole. METHODS: Thirty-four clinical isolates of Sporothrix spp. from Colombia, three from Mexico, and one from Guatemala were identified through sequencing of the noncoding region ITS-1 + 5.8SDNAr + ITS-2 and of the fragment containing exons 3 and 4 of the ß-tubulin gene. Clinical isolate sequences were compared with GenBank reference sequences using the BLASTN tool, and then, phylogenetic analysis was performed. Besides, the in vitro susceptibility to itraconazole was evaluated by determining the minimum inhibitory concentrations according to the CLSI M38-A2 method. RESULTS: Clinical isolates were identified by morphology as Sporothrix spp. Using the molecular markers, ITS and ß-tubulin, isolates were identified as S. schenckii sensu stricto (25) and Sporothrix globosa (13). Susceptibility to itraconazole was variable among clinical isolates. CONCLUSION: This is the first scientific publication that identifies species that cause sporotrichosis in Colombia, along with the antifungal susceptibility to itraconazole.
Assuntos
Antifúngicos/farmacologia , Itraconazol/farmacologia , Sporothrix/classificação , Sporothrix/efeitos dos fármacos , Esporotricose/microbiologia , Aspartato Aminotransferases/sangue , Análise por Conglomerados , Colômbia , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Guatemala , Humanos , México , Testes de Sensibilidade Microbiana , Filogenia , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Sporothrix/genética , Sporothrix/isolamento & purificação , Tubulina (Proteína)/genéticaRESUMO
Mexico is one of the five largest producers of papaya worldwide, but losses caused by pathogens, mainly fungus, at the pre- and post-harvest stages are often more than 50% of the crop. Papaya anthracnose, caused by three different species of the Colletotrichum genus in Mexico, occupies a preponderant place in this problem. Although two of these species, C. gloeosporiodes and C. truncatum, have been characterized morphologically and genotypically, this has not occurred with C. magnum, the third species involved, about which there is very little information. Because of this, it is vital to know its genetic characterization, much more so considering that the studies carried out on the other two species reveal a wide genetic diversity, differences in pathogenicity and in the response to fungicides of the different strains characterized. In this work, Colletotrichum spp. isolates were collected at different papaya orchards in the south-southeast of Mexico. C. magnum isolates identified by species-specific primers were characterized by morphological and molecular approaches. Differences in colony characteristics resulted in five morphological groups. AP-PCR, DAMD and ISSR markers were found to be very efficient for revealing the interspecific variability of this species. The high genetic variability found in the accessions of C. magnum was linked to the geographical area where they were collected. Isolates from Chiapas State were the most variable, showing point mutations in the ITS1-ITS2 region. These results will enable a better phytosanitary management of anthracnose in papaya in this region of Mexico.
Assuntos
Carica/microbiologia , Colletotrichum/genética , Colletotrichum/isolamento & purificação , Impressões Digitais de DNA/métodos , Variação Genética , Sequência de Bases , Colletotrichum/efeitos dos fármacos , Primers do DNA , DNA Fúngico/genética , DNA Ribossômico/genética , Bases de Dados de Ácidos Nucleicos , Fungicidas Industriais/farmacologia , Genótipo , México , Doenças das Plantas/microbiologia , Mutação Puntual , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético , RNA Ribossômico 5,8S/genética , Análise de Sequência , Especificidade da Espécie , VirulênciaRESUMO
Macrolepiota is a poorly known genus in the Neotropics. In order to increase knowledge about this group, we collected specimens from the Atlantic Forest in southern and northeastern Brazil. Macrolepiota cyanolamellata and M. sabulosa from subtropical and tropical regions, respectively, are proposed as new species. We performed molecular phylogenetic analyses of the nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and the combined data set ITS + nuclear large subunit rDNA (28S) + RNA polymerase II second largest (RPB2), as well as morphological analyses. Two lineages with unique morphotypes were found. The species proposed were strongly supported as the sister lineage closely related to M. clelandii and M. subcitrophylla. Detailed descriptions and illustrations of their macro- and microscopic characters are provided.
Assuntos
Agaricales/classificação , Agaricales/genética , Carpóforos/crescimento & desenvolvimento , Filogenia , Agaricales/crescimento & desenvolvimento , Agaricales/isolamento & purificação , Brasil , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Genes de RNAr , Microscopia , Microscopia Eletrônica de Varredura , RNA Polimerase II/genética , RNA Fúngico/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Esporos Fúngicos/citologiaRESUMO
Entamoeba gingivalis is a protozoan that resides in the oral cavity. Using molecular biology techniques, we identified a novel organism that shares the same ecological niche as E. gingivalis. To differentiate this organism from E. gingivalis, we named it "kamaktli variant." By sequencing the 18S-ITS1-5.8S-ITS2 rRNA region, we demonstrated that kamaktli variant is 89% identical to E. gingivalis. To elucidate the relationship between kamaktli variant and E. gingivalis, we performed a phylogenetic analysis. Both taxa clustered in the same clade with high support, indicating that the amoebas are closely related (98/99/1.00, maximum parsimony/maximum likelihood/MrBayes, respectively). Given this information, we propose that these molecular differences between kamaktli variant and E. gingivalis ST1 are sufficient to distinguish them as independent subtypes, and we name the new subtype "E. gingivalis ST2, kamaktli variant."
Assuntos
Entamoeba , Boca/parasitologia , Animais , DNA Espaçador Ribossômico/genética , Entamoeba/classificação , Entamoeba/genética , Entamoeba/isolamento & purificação , Humanos , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 5,8S/genéticaRESUMO
Members of the genus Uvulifer are distributed worldwide and infect aquatic snails and freshwater fishes as first and second intermediate hosts, respectively, and fish-eating birds (kingfishers) as definitive hosts. Metacercariae of Uvulifer spp. were collected from the fins and skin of 20 species of freshwater fishes in Mexico, Guatemala, Honduras, Nicaragua and Costa Rica, and the adults were recovered from the intestine of kingfishers in four localities of Mexico. The genetic divergence among 76 samples (64 metacercariae and 12 adults) was estimated by sequencing the 28S and 5.8S nuclear genes, as well as the internal transcribed spacers ITS1 and ITS2, and one mitochondrial gene (cox1). Maximum likelihood and Bayesian inference analyses inferred with each dataset showed a high genetic diversity within the genus Uvulifer across Middle America, revealing the existence of four genetic lineages that exhibit some level of host specificity to their second intermediate hosts. The metacercariae of lineage 1 were associated with characids and cyprinids in central and northern Mexico. Metacercariae of lineages 2 and 3 were associated with cichlids distributed widely across Middle America. The lack of adults of these lineages in kingfishers, in lineages 2 and 3, or the fact that just a few adult specimens were recovered, as in lineage 1, prevented a formal description of these species. The metacercariae of lineage 4 were found in poeciliids, across a distribution range comprising Mexico, Guatemala, Honduras and Nicaragua, and the adult was found in the green kingfisher in Mexico. The number of specimens sampled for lineage 4, for both gravid adults and metacercariae, allowed us to describe a new species, Uvulifer spinatus n. sp. We describe the new species herein and we discuss briefly the genetic diversity in Uvulifer spp. and the importance of using DNA sequences to properly characterize parasite diversity.
Assuntos
Peixes/parasitologia , Variação Genética , Metacercárias/classificação , Metacercárias/isolamento & purificação , Trematódeos/classificação , Trematódeos/isolamento & purificação , Nadadeiras de Animais/parasitologia , Animais , América Central , Análise por Conglomerados , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Especificidade de Hospedeiro , Metacercárias/anatomia & histologia , Metacercárias/genética , Microscopia , Filogenia , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Trematódeos/anatomia & histologia , Trematódeos/genéticaRESUMO
The family Ceratocoryaceae includes the genera Ceratocorys, Protoceratium, and Schuettiella, whose phylogenetic relationships are poorly known. Here, the new non-yessotoxin-producing species of the genus Ceratocorys, Ceratocorys mariaovidiorum sp. nov., previously reported as the toxic Protoceratium reticulatum, is described from examinations by light and scanning electron microscopy, molecular phylogeny, and toxin analyses. The species description is made from culture samples of strains CCMP1740 and CCMP404 from USA waters. Ceratocorys mariaovidiorum is globular and has thick and strongly reticulated plates with one pore within each reticule, just like P. reticulatum, but the key difference between the two species is the presence of five precingular plates in C. mariaovidiorum instead of six as in P. reticulatum. The thecal plate formula is Po, 4', 0a, 5â³, 6c, ~7s, 5â´, 0p, 2''''. The apical pore plate is oval with a λ-shaped pore. The first apical plate is narrow with a ventral pore on the right anterior side; it contacts the apical pore plate and its contact with the anterior sulcal plate is slight or absent. The fourth precingular plate of other Gonyaulacales is absent. Ceratocorys mariaovidiorum may have small spines on the second antapical plate. A phylogenetic study based on internal transcribed spacer/5.8SrDNA supports the morphological classification of C. mariaovidiorum as a new species of Ceratocorys and in a different clade from P. reticulatum.
Assuntos
Dinoflagellida/classificação , Dinoflagellida/genética , DNA Espaçador Ribossômico/análise , Dinoflagellida/citologia , Dinoflagellida/ultraestrutura , Microscopia Eletrônica de Varredura , Filogenia , RNA de Algas/análise , RNA de Protozoário/análise , RNA Ribossômico 5,8S/análise , Estados UnidosRESUMO
A new genus and species of nematode, Tziminema unachi n. gen., n. sp. is described from the caecum and colon of Baird's tapir Tapirus bairdii (Gill, 1865), found dead in the Reserva de la Biósfera El Triunfo, Chiapas State, in the Neotropical realm of Mexico. Tziminema n. gen. differs from the other nine genera included in the Strongylinae by two main characteristics: having 7-9 posteriorly directed tooth-like structures at the anterior end of the buccal capsule, and the external surface of the buccal capsule being heavily striated. Phylogenetic analyses of the DNA sequences of the mitochondrial cytochrome c oxidase and nuclear DNA, including a partial sequence of the internal transcribed spacer 1, 5.8S and a partial sequence of the internal transcribed spacer 2 of the new taxon, confirmed its inclusion in Strongylinae and its rank as a new genus.
Assuntos
Perissodáctilos/parasitologia , Strongyloidea/classificação , Strongyloidea/isolamento & purificação , Animais , Ceco/parasitologia , Análise por Conglomerados , Colo/parasitologia , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , México , Microscopia , Microscopia Eletrônica de Varredura , Filogenia , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Strongyloidea/anatomia & histologia , Strongyloidea/genéticaRESUMO
The pathological and molecular findings associated with Histomonas meleagridis are described in a leucistic Indian peafowl (Pavo cristatus) from Southern Brazil. The most significant gross findings were multifocal necrotizing hepatitis and diphtheric typhlitis. Histopathologic evaluation of the liver, ceca, kidney, spleen, and small intestine revealed systemic histomoniasis (SH) associated with intralesional and intravascular accumulations of histomonad organisms consistent with H. meleagridis. PCR was used to amplify the DNA of H. meleagridis from the liver, ceca, small intestine, spleen, lungs, and kidneys. Direct sequencing and phylogenetic analyses confirmed that the isolate of the flagellated trichomonad identified from this investigation is more phylogenetically related to H. meleagridis than Tetratrichomonas gallinarum, Tritrichomonas foetus, and Dientamoeba fragilis. These results confirmed the occurrence of SH in this peafowl and add to the diagnosis of this disease in birds from Brazil. This report might represent the first complete identification of spontaneous histomoniasis in a peafowl due to pathological and molecular characteristics and one of the few documented cases of SH in non-commercial birds.
Assuntos
Doenças das Aves/parasitologia , Galliformes , Infecções Protozoárias em Animais/parasitologia , Trichomonadida/isolamento & purificação , Animais , Doenças das Aves/patologia , Brasil , DNA Espaçador Ribossômico/genética , Filogenia , Infecções Protozoárias em Animais/patologia , RNA Ribossômico 5,8S/genética , Trichomonadida/classificação , Trichomonadida/genética , Trichomonadida/fisiologiaRESUMO
Phytomyxea are obligate endoparasites of angiosperm plants and Stramenopiles characterised by a complex life cycle. Here Maullinia braseltonii sp. nov., an obligate parasite infecting the bull kelp Durvillaea (Phaeophyceae, Fucales) from the South-Eastern Pacific (Central Chile and Chiloe Island) and South-Western Atlantic (Falkland Islands, UK) is described. M. braseltonii causes distinct hypertrophies (galls) on the host thalli making it easily identifiable in the field. Sequence comparisons based on the partial 18S and the partial 18S-5.8S-28S regions confirmed its placement within the order Phagomyxida (Phytomyxea, Rhizaria), as a sister species of the marine parasite Maullinia ectocarpii, which is also a parasite of brown algae. The development of resting spores in M. braseltonii is described by light and electron microscopy and confirmed by FISH experiments, which visually showed the differential expression of the 28S non-coding gene, strongly in early plasmodia and weakly in late cysts. M. braseltonii is, so far, the only phytomyxean parasite of brown algae for which the formation of resting spores has been reported, and which is widely distributed in Durvillaea stocks from the Southeastern Pacific and Southwestern Atlantic.
Assuntos
Kelp/parasitologia , RNA de Algas/genética , Rhizaria/classificação , Rhizaria/fisiologia , Chile , Ilhas Malvinas , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Rhizaria/genética , Análise de Sequência de RNARESUMO
Abstract Production of a bioherbicide for biological control of weeds requires a series of steps, from selection of a suitable microbial strain to final formulation. Thus, this study aimed to select fungi for production of secondary metabolites with herbicidal activity using biological resources of the Brazilian Pampa biome. Phytopathogenic fungi were isolated from infected tissues of weeds in the Pampa biome. A liquid synthetic culture medium was used for production of metabolites. The phytotoxicity of fungal metabolites was assessed via biological tests using the plant Cucumis sativus L., and the most promising strain was identified by molecular analysis. Thirty-nine fungi were isolated, and 28 presented some phytotoxic symptoms against the target plant. Fungus VP51 belonging to the genus Diaporthe showed the most pronounced herbicidal activity. The Brazilian Pampa biome is a potential resource for the development of new and sustainable chemical compounds for modern agriculture.