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1.
Mol Ecol ; 28(2): 203-218, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29726053

RESUMEN

Parasites and other symbionts are crucial components of ecosystems, regulating host populations and supporting food webs. However, most symbiont systems, especially those involving commensals and mutualists, are relatively poorly understood. In this study, we have investigated the nature of the symbiotic relationship between birds and their most abundant and diverse ectosymbionts: the vane-dwelling feather mites. For this purpose, we studied the diet of feather mites using two complementary methods. First, we used light microscopy to examine the gut contents of 1,300 individual feather mites representing 100 mite genera (18 families) from 190 bird species belonging to 72 families and 19 orders. Second, we used high-throughput sequencing (HTS) and DNA metabarcoding to determine gut contents from 1,833 individual mites of 18 species inhabiting 18 bird species. Results showed fungi and potentially bacteria as the main food resources for feather mites (apart from potential bird uropygial gland oil). Diatoms and plant matter appeared as rare food resources for feather mites. Importantly, we did not find any evidence of feather mites feeding upon bird resources (e.g., blood, skin) other than potentially uropygial gland oil. In addition, we found a high prevalence of both keratinophilic and pathogenic fungal taxa in the feather mite species examined. Altogether, our results shed light on the long-standing question of the nature of the relationship between birds and their vane-dwelling feather mites, supporting previous evidence for a commensalistic-mutualistic role of feather mites, which are revealed as likely fungivore-microbivore-detritivore symbionts of bird feathers.


Asunto(s)
Enfermedades de las Aves/genética , Código de Barras del ADN Taxonómico/métodos , Plumas/parasitología , Ácaros/genética , Animales , Enfermedades de las Aves/microbiología , Enfermedades de las Aves/parasitología , Aves/genética , Aves/parasitología , Ecosistema , Plumas/microbiología , Microbioma Gastrointestinal/genética , Microscopía , Ácaros/microbiología , Ácaros/patogenicidad , Simbiosis/genética
2.
Microb Ecol ; 78(2): 457-469, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30506480

RESUMEN

Huanglongbing (HLB), caused by Candidatus Liberibacter asiaticus (CLas), an uncultured α-proteobacterium, is the most destructive disease of citrus trees worldwide. In previous studies, trunk injections of penicillin reduced CLas titers and HLB symptoms in citrus. However, antibiotic effects on the whole plant microbial community, which include effects on taxa that interact with CLas, have not yet been addressed. In this study, we investigated the effects of penicillin injection (0, 1000, and 6000 mg L-1) on rhizospheric and endophytic bacterial communities of grapefruit trees in field and greenhouse experiments through culture-independent high-throughput sequencing. DNA extractions from petioles and roots were subjected to 16S rRNA high-throughput sequencing, and reads were clustered by sequence similarity into operational taxonomic units (OTUs). Principal coordinates analysis based on weighted-UniFrac distances did not reveal differences in bacterial communities among treatments in any of the sample sources. However, pairwise linear discriminant analysis indicated significant differences in relative abundance of some taxa (including CLas) among treatments. Network analysis showed that penicillin produced major changes in root bacterial community structure by affecting interspecific microbial associations. This study provides new knowledge of the effect of antimicrobial treatments on interspecific relationships in citrus microbial communities.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Citrus/microbiología , Microbiota/efectos de los fármacos , Penicilinas/farmacología , Enfermedades de las Plantas/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Citrus/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/microbiología , Árboles/efectos de los fármacos , Árboles/microbiología
3.
Plant Dis ; 103(10): 2512-2519, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31432773

RESUMEN

The 16SrIV-D phytoplasma was first identified in Florida in 2006. Since its discovery, it has spread throughout most of the state. It is most prevalent in the central part of Florida, from Hillsborough County on the west coast to St. Lucie County on the east coast. The 16SrIV-D phytoplasma is the causal agent of lethal bronzing disease (LBD), which is also known as Texas Phoenix palm decline (TPPD). It affects a variety of common and economically important ornamental palm species as well as the native and ecologically important species, Sabal palmetto. It has spread into the southern portions of Florida, where the palm species diversity is higher. The aims of this survey were to document the spread of disease in terms of geographic and host range one decade after its introduction into Florida, and to assess the risk that LBD poses to the nursery and landscaping industries. The survey included samples received from stakeholders throughout the state, covering 18 counties, as well as a systematic sampling of palms at the Fort Lauderdale Research and Education Center (FLREC), where the disease is spreading actively. The findings of this survey resulted in the detection of LBD in eight new counties, including Collier, Hernando, Jefferson, Martin, Miami-Dade, Monroe, Seminole, and St. Johns, and the expansion of LBD into four new host species, Cocos nucifera, Livistona chinensis, Butia capitata, and Carpentaria acuminata. These findings are crucial for stakeholders because they highlight new hosts of 16SrIV-D phytoplasma and the geographic expansion of the disease, indicating that vigilance is needed when surveying declining palms.


Asunto(s)
Arecaceae , Especificidad del Huésped , Phytoplasma , Arecaceae/microbiología , Microbiología Ambiental , Florida , Phytoplasma/fisiología , Encuestas y Cuestionarios , Texas
4.
Mol Phylogenet Evol ; 114: 199-211, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28645766

RESUMEN

The study of biological diversification of oomycetes has been a difficult task for more than a century. Pioneer researchers used morphological characters to describe this heterogeneous group, and physiological and genetic tools expanded knowledge of these microorganisms. However, research on oomycete diversification is limited by conflicting phylogenies. Using whole genomic data from 17 oomycete taxa, we obtained a dataset of 277 core orthologous genes shared among these genomes. Analyses of this dataset resulted in highly congruent and strongly supported estimates of oomycete phylogeny when we used concatenated maximum likelihood and coalescent-based methods; the one important exception was the position of Albugo. Our results supported the position of Phytopythium vexans (formerly in Pythium clade K) as a sister clade to the Phytophthora-Hyaloperonospora clade. The remaining clades comprising Pythium sensu lato formed two monophyletic groups. One group was composed of three taxa that correspond to Pythium clades A, B and C, and the other group contained taxa representing clades F, G and I, in agreement with previous Pythium phylogenies. However, the group containing Pythium clades F, G and I was placed as sister to the Phytophthora-Hyaloperonospora-Phytopythium clade, thus confirming the lack of monophyly of Pythium sensu lato. Multispecies coalescent methods revealed that the white blister rust, Albugo laibachii, could not be placed with a high degree of confidence. Our analyses show that genomic data can resolve the oomycete phylogeny and provide a phylogenetic framework to study the evolution of oomycete lifestyles.


Asunto(s)
Oomicetos/clasificación , ADN/química , ADN/aislamiento & purificación , ADN/metabolismo , Genoma , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Oomicetos/genética , Filogenia , Pythium/clasificación , Pythium/genética , Análisis de Secuencia de ADN
5.
J Med Entomol ; 51(1): 139-44, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24605463

RESUMEN

The human head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), is an obligate ectoparasite that causes pediculosis capitis and has parasitized humans since the beginning of humankind. Head louse infestations are widespread throughout the world and have been increasing since the early 1990s partially because of ineffective pediculicides. In Argentina, the overuse of products containing pyrethroids has led to the development of resistant louse populations. Pyrethroid insecticides act on the nervous system affecting voltage-sensitive sodium channels. Three point mutations at the corresponding amino acid sequence positions M815I, T917I, and L920F in the voltage-gated sodium channel gene are responsible for contributing to knockdown resistance (kdr). The management of pyrethroid resistance requires either early detection or the characterization of the mechanisms involved in head louse populations. In the current study, we estimated the distribution of kdr alleles in 154 head lice from six geographical regions of Argentina. Pyrethroid resistance kdr alleles were found in high frequencies ranging from 67 to 100%. Of these, 131 (85.1%) were homozygous resistant, 13 (8.4%) were homozygous susceptible, and 10 (6.5%) were heterozygous. Exact tests for the Hardy-Weinberg equilibrium for each location showed that genotype frequencies differed significantly from expectation in four of the six sites studied. These results show that pyrethroid resistance is well established reaching an overall frequency of 88%, thus close to fixation. With 30 yr of pyrethroid-based pediculicides use in Argentina, kdr resistance has evolved rapidly among these head louse populations.


Asunto(s)
Insecticidas , Pediculus/genética , Piretrinas , Canales de Sodio Activados por Voltaje/genética , Animales , Argentina , Niño , Geografía , Humanos , Resistencia a los Insecticidas/genética
6.
J Med Entomol ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38635291

RESUMEN

The cosmopolitan ectoparasite human head louse, Pediculus humanus capitis (De Geer)(Phthiraptera:Pediculidae), affects mostly school-aged children, with infestations reported every year mainly due to louse resistance to pyrethroids. One of the main resistance mechanisms of pyrethroids is the target site insensitivity (kdr), which is caused by single-nucleotide point mutations (SNPs) located in the voltage-sensitive sodium channel gene. In this study, we analyzed individual head lice toxicologically via the description of their susceptibility profile to permethrin and genetically through the genotypification of their kdr alleles as well as nuclear microsatellite loci. Lice were collected from 4 schools in the city of Buenos Aires, Argentina. The resistance ratios varied from 33.3% to 71.4%, with a frequency of the T917I kdr mutation of 87.31% and with 83.6% of the head lice being homozygous resistant to pyrethroids. Microsatellite data indicated that all the louse school populations had genotype proportions that deviated from Hardy-Weinberg expectations, with FIS > 0 reflecting a deficit of heterozygotes. Bottleneck analysis suggested that all louse school populations underwent a recent reduction in population sizes, while 3 of the 4 schools had gene flow values around 1, indicating ongoing gene flow among those schools. Our study suggests that school louse populations in the city of Buenos Aires may form a metapopulation, where each school represents a small population that undergoes extinction and recolonization processes under strong permethrin selection. This is the first multilevel analysis integrating toxicological, kdr-genotyping, and microsatellite data in human louse populations.

7.
Am J Phys Anthropol ; 152(1): 118-29, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23900879

RESUMEN

Anthropological studies suggest that the genetic makeup of human populations in the Americas is the result of diverse processes including the initial colonization of the continent by the first people plus post-1492 European migrations. Because of the recent nature of some of these events, understanding the geographical origin of American human diversity is challenging. However, human parasites have faster evolutionary rates and larger population sizes allowing them to maintain greater levels of genetic diversity than their hosts. Thus, we can use human parasites to provide insights into some aspects of human evolution that may be unclear from direct evidence. In this study, we analyzed mitochondrial DNA (mtDNA) sequences from 450 head lice in the Americas. Haplotypes clustered into two well-supported haplogroups, known as A and B. Haplogroup frequencies differ significantly among North, Central and South America. Within each haplogroup, we found evidence of demographic expansions around 16,000 and 20,000 years ago, which correspond broadly with those estimated for Native Americans. The parallel timing of demographic expansions of human lice and Native Americans plus the contrasting pattern between the distribution of haplogroups A and B through the Americas suggests that human lice can provide additional evidence about the human colonization of the New World.


Asunto(s)
ADN Mitocondrial/genética , Infestaciones por Piojos/parasitología , Pediculus/clasificación , Américas , Análisis de Varianza , Animales , Antropología Física , Ciclooxigenasa 1/genética , ADN Mitocondrial/análisis , Emigración e Inmigración , Evolución Molecular , Genes de Insecto , Variación Genética , Haplotipos , Humanos , Pediculus/genética , Filogenia
8.
PLoS One ; 18(11): e0293409, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37939041

RESUMEN

The human louse, Pediculus humanus, is an obligate blood-sucking ectoparasite that has coevolved with humans for millennia. Given the intimate relationship between this parasite and the human host, the study of human lice has the potential to shed light on aspects of human evolution that are difficult to interpret using other biological evidence. In this study, we analyzed the genetic variation in 274 human lice from 25 geographic sites around the world by using nuclear microsatellite loci and female-inherited mitochondrial DNA sequences. Nuclear genetic diversity analysis revealed the presence of two distinct genetic clusters I and II, which are subdivided into subclusters: Ia-Ib and IIa-IIb, respectively. Among these samples, we observed the presence of the two most common louse mitochondrial haplogroups: A and B that were found in both nuclear Clusters I and II. Evidence of nuclear admixture was uncommon (12%) and was predominate in the New World potentially mirroring the history of colonization in the Americas. These findings were supported by novel DIYABC simulations that were built using both host and parasite data to define parameters and models suggesting that admixture between cI and cII was very recent. This pattern could also be the result of a reproductive barrier between these two nuclear genetic clusters. In addition to providing new evolutionary knowledge about this human parasite, our study could guide the development of new analyses in other host-parasite systems.


Asunto(s)
Infestaciones por Piojos , Pediculus , Animales , Humanos , Femenino , Pediculus/genética , Filogenia , Infestaciones por Piojos/genética , Infestaciones por Piojos/parasitología , ADN Mitocondrial/genética , Variación Genética
9.
Insects ; 14(2)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36835687

RESUMEN

This study aims to evaluate the effectiveness of our outreach program "The ImportANTs of ANTs" in communicating scientific topics to elementary school children, using ants as example organisms. In this program's first phase, we focused on the concepts of native and invasive species and how invasive species affect ecosystems. The program included various active learning approaches, including presentations, handouts, crafts, and live colony viewings. At two schools (one in rural and one in suburban areas), 210 students from 5th grade were assessed using short, anonymous pre- and post-surveys. We analyzed the students' responses to questions from the following categories: general feelings about ants, ant knowledge, general care for the environment, general impact knowledge, and native/invasive species knowledge. The school populations displayed distinct opinion changes and knowledge gains; however, there was a significant increase in knowledge of native and invasive species in both populations. Our study demonstrates that ants are good models to teach children about the impact of invasive species. The project aims to drive universal responsibility by forging proactive attitudes toward protecting the environment and native species early.

10.
Insects ; 14(12)2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-38132575

RESUMEN

Microsporidia are natural pathogens of arthropods and have been used as biological control against insect pests. In the United States, efforts to control the invasive Red Imported Fire Ant, Solenopsis invicta, and Black Imported Fire Ant, Solenopsis richteri, have included the use of the microsporidium, Kneallhazia solenopsae. However, there is limited information about the genetic differences among the microsporidian variants found in S. invicta and in S. richteri. In this study, we assessed the prevalence and genetic diversity of K. solenopsae in native populations of S. richteri in Argentina (South America). Additionally, we examined the social parasitic ant, Solenopsis daguerrei, which is found in some S. richteri nests, for the presence of this microsporidium. The survey of 219 S. richteri nests revealed K. solenopsae infections in all five sites analyzed, with 28 colonies (12.8%) positive for the microsporidium. Among the 180 S. daguerrei individuals collected, seven ants (3.9%) from three sites tested positive for K. solenopsae. Phylogenetic analyses of the microsporidian variants present in S. richteri and S. daguerrei based on partial small subunit ribosomal gene sequences (SSU rRNA) showed that both ant species shared the same variant, which is different from the ones found in S. invicta. Further studies are needed to determine the pathogenicity of genetically different K. solenopsae variants among Solenopsis species.

11.
Mol Ecol ; 21(4): 817-33, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22181975

RESUMEN

We characterized patterns of genetic variation in populations of the fire ant Solenopsis invicta in China using mitochondrial DNA sequences and nuclear microsatellite loci to test predictions as to how propagule pressure and subsequent dispersal following establishment jointly shape the invasion success of this ant in this recently invaded area. Fire ants in Wuchuan (Guangdong Province) are genetically differentiated from those found in other large infested areas of China. The immediate source of ants in Wuchuan appears to be somewhere near Texas, which ranks first among the southern USA infested states in the exportation of goods to China. Most colonies from spatially distant, outlying areas in China are genetically similar to one another and appear to share a common source (Wuchuan, Guangdong Province), suggesting that long-distance jump dispersal has been a prevalent means of recent spread of fire ants in China. Furthermore, most colonies at outlier sites are of the polygyne social form (featuring multiple egg-laying queens per nest), reinforcing the important role of this social form in the successful invasion of new areas and subsequent range expansion following invasion. Several analyses consistently revealed characteristic signatures of genetic bottlenecks for S. invicta populations in China. The results of this study highlight the invasive potential of this pest ant, suggest that the magnitude of international trade may serve as a predictor of propagule pressure and indicate that rates and patterns of subsequent range expansion are partly determined by the interplay between species traits and the trade and transportation networks.


Asunto(s)
Hormigas/genética , Variación Genética , Genética de Población , Especies Introducidas , Animales , Hormigas/fisiología , Núcleo Celular/genética , China , ADN Mitocondrial/genética , Genotipo , Repeticiones de Microsatélite , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Conducta Social , Texas
12.
Syst Biol ; 59(2): 162-84, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20525628

RESUMEN

Species delimitation has been invigorated as a discipline in systematics by an influx of new character sets, analytical methods, and conceptual advances. We use genetic data from 68 markers, combined with distributional, bioclimatic, and coloration information, to hypothesize boundaries of evolutionarily independent lineages (species) within the widespread and highly variable nominal fire ant species Solenopsis saevissima, a member of a species group containing invasive pests as well as species that are models for ecological and evolutionary research. Our integrated approach uses diverse methods of analysis to sequentially test whether populations meet specific operational criteria (contingent properties) for candidacy as morphologically cryptic species, including genetic clustering, monophyly, reproductive isolation, and occupation of distinctive niche space. We hypothesize that nominal S. saevissima comprises at least 4-6 previously unrecognized species, including several pairs whose parapatric distributions implicate the development of intrinsic premating or postmating barriers to gene flow. Our genetic data further suggest that regional genetic differentiation in S. saevissima has been influenced by hybridization with other nominal species occurring in sympatry or parapatry, including the quite distantly related Solenopsis geminata. The results of this study illustrate the importance of employing different classes of genetic data (coding and noncoding regions and nuclear and mitochondrial DNA [mtDNA] markers), different methods of genetic data analysis (tree-based and non-tree based methods), and different sources of data (genetic, morphological, and ecological data) to explicitly test various operational criteria for species boundaries in clades of recently diverged lineages, while warning against over reliance on any single data type (e.g., mtDNA sequence variation) when drawing inferences.


Asunto(s)
Hormigas/clasificación , Hormigas/genética , Clasificación/métodos , Flujo Génico/genética , Variación Genética , Filogenia , Animales , Teorema de Bayes , Brasil , Simulación por Computador , Demografía , Frecuencia de los Genes , Genotipo , Isoenzimas/genética , Funciones de Verosimilitud , Repeticiones de Microsatélite/genética , Modelos Genéticos , Especificidad de la Especie
13.
J Invertebr Pathol ; 105(3): 279-88, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20691187

RESUMEN

Kneallhazia solenopsae is a pathogenic microsporidium that infects the fire ants Solenopsis invicta and Solenopsis richteri in South America and the USA. In this study, we analyzed the prevalence and molecular diversity of K. solenopsae in fire ants from North and South America. We report the first empirical evidence of K. solenopsae infections in the tropical fire ant, Solenopsis geminata, and S. geminata×Solenopsis xyloni hybrids, revealing an expanded host range for this microsporidium. We also analyzed the molecular diversity at the 16S ribosomal RNA gene in K. solenopsae from the ant hosts S.invicta, S. richteri, S. geminata and S. geminata×S. xyloni hybrids from North America, Argentina and Brazil. We found 22 16S haplotypes. One of these haplotypes (WD_1) appears to be widely distributed, and is found in S. invicta from the USA and S. geminata from southern Mexico. Phylogenetic analyses of 16S sequences revealed that K. solenopsae haplotypes fall into one of two major clades that are differentiated by 2-3%. In some cases, multiple K. solenopsae haplotypes per colony were found, suggesting either an incomplete homogenization among gene copies within the 16S gene cluster or multiple K. solenopsae variants simultaneously infecting host colonies.


Asunto(s)
Hormigas/microbiología , Microsporidios/genética , Microsporidiosis/epidemiología , Animales , Secuencia de Bases , Genes Fúngicos/genética , Haplotipos , Microsporidia no Clasificados/genética , Microsporidiosis/genética , Datos de Secuencia Molecular , América del Norte , Filogenia , Prevalencia , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
J Insect Sci ; 10: 73, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20673191

RESUMEN

Two distinct forms of colony social organization occur in the fire ant Solenopsis invicta Buren (Hymenoptera: Formicidae): colonies of the monogyne social form are headed by a single egg-laying queen, whereas those of the polygyne social form contain multiple egg-laying queens. This major difference in social organization is associated with genetic variation at a single gene (Gp-9) whereby all polygyne queens possess at least one b-like allele, while monogyne queens lack such b-like alleles and instead harbor B-like alleles only. Further, a recent study of native populations revealed that all b-like alleles in polygyne queens consistently contain three diagnostic amino acid residues: possession of only one or two of these critical residues is not sufficient for polygyny. TaqMan allelic discrimination assays were developed to survey the variable nucleotide sites associated with these three critical amino acid residues. The assays were validated by surveying nests of known social form from the species' introduced in the USA and from native South American ranges, as well as by comparing the results to Gp-9 sequence data from a subset of samples. The results demonstrate these new molecular assays consistently and accurately identify the variable nucleotides at all three sites characteristic of the B-like and b-like Gp-9 allele classes, allowing for accurate determination of colony social form.


Asunto(s)
Hormigas/genética , Conducta Animal/fisiología , Entomología/métodos , Técnicas Genéticas , Conducta Social , Animales , Femenino , Técnicas Genéticas/normas , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple/genética
15.
Front Physiol ; 11: 566968, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33071821

RESUMEN

Corals' obligate association with unicellular dinoflagellates, family Symbiodiniaceae form the foundation of coral reefs. For nearly a century, researchers have delved into understanding the coral-algal mutualism from multiple levels of resolution and perspectives, and the questions and scope have evolved with each iteration of new techniques. Advances in genetic technologies not only aided in distinguishing between the multitude of Symbiodiniaceae but also illuminated the existence and diversity of other organisms constituting the coral microbiome. The coral therefore is a meta-organism, often referred to as the coral holobiont. In this review, we address the importance of including a holistic perspective to understanding the coral holobiont. We also discuss the ramifications of how different genotypic combinations of the coral consortium affect the holobiont entity. We highlight the paucity of data on most of the coral microbiome. Using Symbiodiniaceae data, we present evidence that the holobiont properties are not necessarily the sum of its parts. We then discuss the consequences of the holobiont attributes to the fitness of the holobiont and the myriad of organisms that contribute to it. Considering the complexity of host-symbiont genotypic combinations will aid in our understanding of coral resilience, robustness, acclimation, and/or adaptation in the face of environmental change and increasing perturbations.

16.
Zootaxa ; 4763(1): zootaxa.4763.1.4, 2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-33056878

RESUMEN

An ongoing survey for planthoppers associated with palms in the Caribbean basin is being conducted with current efforts on the Caribbean lowlands of Costa Rica. In an expedition in June of 2019, a derbid was found on coconut palms in Alajuela province and was determined to be a new species belonging to the genus Anotia. The novel taxon is described and named Anotia firebugia Bahder Bartlett sp. n. Additionally, molecular barcode data (COI) is provided for the newly described taxon.


Asunto(s)
Hemípteros , Animales , Cocos , Costa Rica
17.
Zootaxa ; 4718(4): zootaxa.4718.4.6, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-32230007

RESUMEN

An ongoing survey for novel phytoplasmas and viruses that affect palms (Arecaceae) and their potential vectors is being conducted in Costa Rica. During that survey, a new species of derbid planthopper (Hemiptera: Fulgoroidea) from the palm Astrocaryum alatum H.F. Loomis was found in Heredia State and is here described as Agoo dahliana sp. n. Omolicna dubia Caldwell and O. latens Fennah were also found on coconut palms (Cocos nucifera L.) and represent new country records. Sequence data for the cytochrome c oxidase subunit I (COI) were generated for 9 ingroup (Omolicna Fennah) and 1 outgroup (Neocenchrea Metcalf) taxa; and for 18S ribosomal RNA gene were generated for 8 ingroup plus 2 outgroup taxa (Neocenchrea, Cenchrea Westwood). These data were compiled with available data from GenBank and BOLD for maximum likelihood phylogenetic reconstruction for Omolicna. These results, plus morphological evidence, support changing the status of the genus-group name Agoo Bahder Bartlett from subgenus within Omolicna to full genus, resulting in the new combination of Agoo xavieri Bahder Bartlett. Based on the original description and illustration of the genitalia of Omolicna rubrimarginata Fennah (from Trinidad), we transfer this species to Agoo, creating the combination Agoo rubrimarginata (Fennah), and bringing the total number of species in this genus to three, with A. dahliana sp. n. and A. xavieri currently only known from Costa Rica. Based on both molecular and morphological evidence, O dubia is transferred to Anchimothon Fennah. A key to differentiate the species of Agoo is presented.


Asunto(s)
Hemípteros , Animales , Cocos , Costa Rica , Filogenia
18.
Mycologia ; 112(5): 921-931, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32703099

RESUMEN

Environmentally damaging invasive plants can also serve as reservoir hosts for agricultural pathogens. Microstegium vimineum is an invasive C4 annual grass that is present throughout the midwestern and eastern United States. It can reach high densities in disturbed areas such as crop-forest interfaces, which creates the potential for pathogen spillover from M. vimineum to agricultural crops and native plants. A previous study that surveyed disease on M. vimineum found a large-spored Bipolaris species that was widespread on M. vimineum and also isolated from co-occurring native grasses. Here, we report that the large-spored fungus isolated from M. vimineum and the native grass Elymus virginicus is Drechslera gigantea, based on comparison with published descriptions of morphological traits, and establish that D. gigantea is a pathogen of M. vimineum and E. virginicus. We review the phylogenetic placement and taxonomic history of D. gigantea and propose that it be reassigned to the genus Bipolaris as Bipolaris gigantea.


Asunto(s)
Ascomicetos/clasificación , Ascomicetos/citología , Ascomicetos/genética , Bipolaris/clasificación , Bipolaris/genética , Especies Introducidas , Poaceae/microbiología , Ascomicetos/patogenicidad , Bipolaris/citología , Bipolaris/patogenicidad , Filogenia , Enfermedades de las Plantas/clasificación , Enfermedades de las Plantas/genética , Análisis de Secuencia de ADN , Estados Unidos
19.
Zootaxa ; 4577(3): zootaxa.4577.3.5, 2019 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-31715711

RESUMEN

An ongoing survey for novel phytoplasmas and viruses that affect palms (Arecaceae) is being conducted in Costa Rica along with potential vectors. During that survey, a new species of derbid planthopper (Hemiptera: Fulgoroidea) in the genus Omolicna Fennah was detected from Heredia and Limón State and is here described as Omolicna xavieri sp. n. This new taxon was first found on declining coconut palms (Cocos nucifera) and subsequently on healthy coconut palms in Tortuguero National Park. Also, two additional species of Omolicna, O. brunnea and O. triata, were collected on coconut in the same habitat and represent new country records. There are no previously published records of Omolicna from Costa Rica. Sequence data for the cytochrome c oxidase subunit I (COI) and the 18S ribosomal RNA gene were obtained. In addition, novel 18S primers specific to auchenorrhynchan insects were developed and presented. The molecular data show high pairwise distances between O. xavieri sp. n. and other Omolicna species (24% to 31% and 10% using COI and 18S, respectively). Based on both morphological and sequence data, we erect and briefly describe the new subgenus Agoo for the new species to reflect the observed differences. A checklist of Omolicna species is presented.


Asunto(s)
Arecaceae , Hemípteros , Animales , Cocos , Costa Rica
20.
Zootaxa ; 4701(1): zootaxa.4701.1.5, 2019 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-32229968

RESUMEN

Myxia belinda gen. et sp. nov. is established for a new taxon of Cixiidae in the tribe Oecleini collected from palms in Costa Rica. The new taxon was discovered while surveying palms for potential phytoplasma vectors. Placement in a new genus is supported by a 1,383 bp sequence of 18S that differs by 2.77% from Haplaxius, 5.20% from Myndus taffini, and 2.80% from Nymphomyndus caribbea. Intrageneric variation for 18S was found to be approximately 0.5% to 0.6% within Haplaxius. Generic level differences within the Oecleini for COI ranged from 15% to 17% with the novel taxon differing by about 16% from other genera. The new genus is most similar in appearance to Haplaxius but possesses striking sexual dimorphism, and the aedeagus is only partially surrounded by the phallobase (versus entirely enveloped in Haplaxius). The discovery of a novel taxon of cixiid on palms that is similar to Haplaxius is important because of the role that Haplaxius crudus plays in phytoplasma transmission in palm agro- and natural ecosystems.


Asunto(s)
Hemípteros , Animales , Costa Rica , Ecosistema , Bosques , Los Angeles
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