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110 resultados encontrados para: TEMA: Filogenética
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1.
Artículo
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Accessing cryptic diversity in Neotropical rattlesnakes (Serpentes: Viperidae: Crotalus) with the description of two new species
Carbajal Márquez, Rubén Alonso (autor) ; Cedeño-Vázquez, J.R. (autor) ; Martínez Arce, Arely (autora) ; Neri Castro, Edgar (autor) ; Machkour M'Rabet, Salima (autora) ;
Contenido en: Zootaxa Vol. 4729, no. 4 (January 2020), p. 451-481 ISSN: 1175-5334
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Resumen en español

Los miembros del complejo de especies Crotalus durissus tienen una amplia distribución desde México hasta Argentina, principalmente en zonas con bosque tropical deciduo. Aunque se reconocen actualmente cuatro especies (C. culminatus, C. durissus, C. simus y C. tzabcan), los límites entre estas no son claros. Estudios genéticos previos sugieren que C. durissus y C. simus pueden ser parafiléticos y que al menos una especie críptica puede estar presente. Analizamos una secuencia de 2596 pares de bases de ADN provenientes de tres genes mitocondriales y uno nuclear, para inferir las relaciones filogenéticas en las especies de víboras de cascabel neotropicales. Por otro lado, se examinaron especímenes de museo, silvestres y ejemplares en cautiverio para analizar caracteres morfológicos. Nuestros resultados sugieren que la taxonomía actual del grupo de especies Crotalus durissus no refleja su historia evolutiva. Los resultados obtenidos muestran un fuerte apoyo para cinco linajes independientes en Crotalus simus (sensu lato) con evidencia genética y morfológica para tres taxones previamente reconocidos y dos especies nuevas, y tres linajes en C. durissus, que representan hipótesis de especies para ser probadas con evidencia adicional. También encontramos apoyo para mantener a C. totonacus en el complejo de especies Crotalus molossus. Sugerimos cambios taxonómicos conservadores para el complejo y especies relacionadas, pero se necesita más evidencia (e.g., morfología, ecología y composición bioquímica del veneno), para aclarar las relaciones entre especies.

Resumen en inglés

Members of the Crotalus durissus species complex are widely distributed from Mexico to Argentina in areas with mainly seasonally dry tropical deciduous forest. Although four species (C. culminatus, C. durissus, C. simus and C. tzabcan) are currently recognized, species limits remain to be tested. Previous genetic studies suggest that C. durissus and C. simus may be paraphyletic and that at least one cryptic species may be present. We analyzed 2596 bp of DNA sequence data from three mitochondrial and one nuclear gene to infer phylogenetic relationships in the Neotropical rattlesnakes. We also examined museum and wild specimens as well as captive animals to analyze morphological characters. Our results suggest that current taxonomy of the Crotalus durissus species complex does not reflect evolutionary history. We found strong support for five independent lineages within Crotalus simus (sensu lato), with genetic and morphological evidence for three previously recognized taxa and two new species, as well as three major lineages within C. durissus that each represent species hypothesis to be tested with additional evidence. We also found support to retain C. totonacus in the Crotalus molossus species complex. We suggest conservative taxonomic changes to the complex and related species, but more evidence is needed (e.g., morphology, ecology and venom composition) to clarify relationships among species.


2.
Artículo
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Resumen en: Inglés |
Resumen en inglés

Insect β-1,3-glucanases belong to Glycoside Hydrolase Family 16 (GHF16) and are involved in digestion of detritus and plant hemicellulose. In this work, we investigated the role of GHF16 genes in Aedes aegypti larvae, due to their detritivore diet. Aedes aegypti genome has six genes belonging to GHF16 (Aae GH16.1 – Aae GH16.6), containing two to six exons. Sequence analysis suggests that five of these GHF16 sequences (Aae GH16.1, 2, 3, 5, and 6) contain the conserved catalytic residues of this family and correspond to glucanases. All genomes of Nematocera analyzed showed putative gene duplications corresponding to these sequences. Aae GH16.4 has no conserved catalytic residues and is probably a β-1,3-glucan binding protein involved in the activation of innate immune responses. Additionally, Ae. aegypti larvae contain significant β-1,3-glucanase activities in the head, gut and rest of body. These activities have optimum pH about 5–6 and molecular masses between 41 and 150 kDa. All GHF16 genes above showed different levels of expression in the larval head, gut or rest ofthebody. Knock-down of AeGH16.5 resulted in survival and pupation rates lower than controls (dsGFP and water treated). However, under stress conditions, severe mortalities were observed in AeGH16.1 and AeGH16.6 knocked-down larvae. Enzymatic assays of β-1,3-glucanase in AeGH16.5 silenced larvae exhibited lower activity in the gut and no change in the rest of the body. Chromatographic activity profiles from gut samples after GH16.5 silencing showed suppression of enzymatic activity, suggesting that this gene codes for the digestive larval β-1,3-glucanase of Ae. aegypti. This gene and enzyme are attractive targets for new control strategies, based on the impairment of normal gut physiology.


Resumen en: Inglés |
Resumen en inglés

Twenty-nine DNA regions of plastid origin have been previously identified in the mitochondrial genome of Cucurbita pepo (pumpkin; Cucurbitaceae). Four of these regions harbor homolog sequences of rbcL, matK, rpl20–rps12 and trnL–trnF, which are widely used as molecular markers for phylogenetic and phylogeographic studies. We extracted the mitochondrial copies of these regions based on the mitochondrial genome of C. pepo and, along with published sequences for these plastome markers from 13 Cucurbita taxa, we performed phylogenetic molecular analyses to identify inter-organellar transfer events in the Cucurbita phylogeny and changes in their nucleotide substitution rates. Phylogenetic reconstruction and tree selection tests suggest that rpl20 and rbcL mitochondrial paralogs arose before Cucurbita diversification whereas the mitochondrial matK and trnL–trnF paralogs emerged most probably later, in the mesophytic Cucurbita clade. Nucleotide substitution rates increased one order of magnitude in all the mitochondrial paralogs compared to their original plastid sequences. Additionally, mitochondrial trnL–trnF sequences obtained by PCR from nine Cucurbita taxa revealed higher nucleotide diversity in the mitochondrial than in the plastid copies, likely related to the higher nucleotide substitution rates in the mitochondrial region and loss of functional constraints in its tRNA genes.


4.
Artículo
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Resumen en inglés

Background: Ticks are a problem for cattle production mainly in tropical and subtropical regions, because they generate great economic losses. Acaricides and vaccines have been used to try to keep tick populations under control. This has been proven difficult given the resistance to acaricides and vaccines observed in ticks. Resistance to protein rBm86-based vaccines has been associated with the genetic diversity of Bm86 among the ectoparasite’spopulations. So far, neither genetic diversity, nor spatial distribution of circulating Bm86 haplotypes, have been studied within the Mexican territory. Here, we explored the genetic diversity of 125 Bm86 cDNA gene sequences from R. microplusfrom 10 endemic areas of Mexico by analyzing haplotype distribution patterns to help in understanding the population genetic structure of Mexican ticks. Results: Our results showed an average nucleotide identity among the Mexican isolates of 98.3%, ranging from 91.1 to 100%. Divergence between the Mexican and Yeerongpilly (the Bm86 reference vaccine antigen) sequences ranged from 3.1 to 7.4%. Based on the geographic distribution of Bm86 haplotypes in Mexico, our results suggest gene flow occurrence within different regions of the Mexican territory, and even the USA. Conclusions: The polymorphism of Bm86 found in the populations included in this study, could account for thepoor efficacy of the current Bm86 antigen based commercial vaccine in many regions of Mexico. Our data may contribute towards designing new, highly-specific, Bm86 antigen vaccine candidates against R. microplus circulatingin Mexico.


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Resumen en inglés

The genus Schizophyllum is easily recognized within the order Agaricales. However, at the species level, taxonomic information for identification purposes is limited. The objective of the present study was to confirm the identity of the Schizophyllum species present in Tabasco, Mexico, by means of a detailed taxonomic revision of the macro-and micromorphological characters in more than 90 specimens, as well as phylogenetic analyses inferred from ITS sequence data. In total, three Schizophyllum species are described, of which one constitute a new record for Mexico. Finally, the edibility of S. radiatum is reported for the first time in the humid tropical region.


6.
Libro
Perspectivas de investigación sobre los mamíferos silvestres de Guatemala / edición: Cristian Kraker, Ana Patricia Calderón, Andrea A. Cabrera
Disponible en línea: Perspectivas de investigación sobre los mamíferos silvestres de Guatemala.
Kraker Castañeda, Cristian (editor) ; Calderón, Ana Patricia (editora) ; Cabrera, Andrea A. (editora) ;
Guatemala, Guatemala : Asociación Guatemalteca de Mastozoologos , 2019
Disponible en línea
Clasificación: EE/599.097281 / P4
Bibliotecas: San Cristóbal , Tapachula
Cerrar
SIBE San Cristóbal
ECO010019774 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Tapachula
ECO020013863 (Disponible)
Disponibles para prestamo: 1
PDF
Índice | Resumen en: Español |
Resumen en español

Desde hace décadas se han llevado a cabo estudios enfocados a los mamíferos silvestres de Guatemala; sin embargo, mucha de esta información permanece como literatura gris. Hasta ahora, no existía una obra que recopilara trabajos científicos sobre este taxón. Habiendo identificado esta oportunidad decidimos, con apoyo de la Asociación Guatemalteca de Mastozoólogos, convocar a un grupo de investigadores/as para que desarrollaran con libertad manuscritos en su área de especialización y de esta manera compilar perspectivas, planteamientos y herramientas variadas. Finalmente, se logra integrar textos que comprenden a los mamíferos terrestres menores, mamíferos terrestres medianos y mayores, y mamíferos acuáticos continentales y marinos. Los mismos son inéditos y estuvieron sujetos a revisión por pares, cumpliendo de esta manera con una de las premisas más importantes en el ámbito de la publicación científica, la retroalimentación entre especialistas. Es así, que concretamos este proyecto cuyo impacto se puede extender a instituciones académicas y gubernamentales, ya que brinda en algunos casos la base de conocimiento, así como insumos para las estrategias de conservación de biodiversidad.

Índice

Prólogo
Presentación
Introducción
Listado de autores/as
Listado de revisores/as
Mamíferos Terrestres Pequeños
Shrews (Eulipotyphla, Soricidae) of Guatemala
Abstract
Introduction
Reproductive patterns
Taxonomic Accounts
Accounts of species
Acknowledgments
Literature cited
Diversification Patterns of Gricetid Rodents in Mesoamerica
Abstract
Introduction
Materials and methods
Results
Discussion
Acknowledgments
Literature cited
Actividad reproductiva en 41 especies de murciélagos de 4 biomas de Guatemala
Resumen
Introducción
Materiales y métodos
Resultados
Discusión
Agradecimientos
Literatura citada
Anexos
Mamíferos Terrestres Medianos y Grandes
Estado de conservación de dos ungulados sociales en Guatemala: pecarí de labios blancos y pecarí de collar
Resumen
Introducción
Materiales y métodos
Resultados
Discusión
Agradecimientos
Literatura citada
Estado de conservación del venado cola blanca, el cabrito rojo y el cabro bayo en Guatemala, en la Reserva de Biosfera Calakmul y el ejido Nuevo Becal, México
Resumen
Introducción
Materiales y métodos
Resultados
Discusión
Agradecimientos
Literatura citada
Historia natural y conservación del tapir centroamericano (Tapirus bairdii) en Guatemala
Resumen
Introducción
Materiales y métodos
Resultados
Discusión
Agradecimientos
Literatura citada
Laying the Foundations: Distribution of Game and Jaguar Prey Species in Response to Subsistence Hunting in the Eastern Maya Biosphere Reserve
Abstract
Introduction
Materials and methods
Results
Discussion
Acknowledgements
Literature cited
Situación de los primates en Petén, Guatemala
Resumen
Introducción
Materiales y métodos
Resultados
Discusión
Agradecimientos
Literatura citada
Anexos

Mamíferos Acuáticos Continentales y Marinos
El manatí antillano Trichechus manatus manatus (Sirenia: Trichechidae) en Guatemala: amenazas y procesos de conservación
Resumen
Introducción
Materiales y métodos
Resultados
Discusión
Agradecimientos
Literatura citada
Familia Delphinidae en Guatemala: avances en el conocimiento sobre su distribución y comportamiento
Resumen
Introducción
Materiales y métodos
Resultados
Discusión
Agradecimientos
Literatura citada
Anexos
Distribución y abundancia de las ballenas en Guatemala con énfasis en el comportamiento de la ballena jorobada (Megaptera novaeangliae)
Resumen
Introducción
Materiales y métodos
Resultados
Discusión
Agradecimientos
Literatura citada


7.
Artículo
Phylogeny of Microphthalminae hartmann-Schröder, 1971, and revision of Hesionella hartman, 1939, and Struwela hartmann-Schröder, 1959 (Annelida, Errantia)
Salazar Vallejo, Sergio I. (autor) ; León González, Jesús Ángel de (autor) ; Carrera Parra, Luis Fernando (autor) ;
Disponible en línea
Contenido en: PeerJ Volumen 7, número e7723 (2019), p. 1-35 ISSN: 2167-8359
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Resumen en inglés

Microphthalminae Hartmann-Schröder, 1971 was proposed in Hesionidae to include Microphthalmus and Hesionides; however, the affinities of these genera to other members of Hesionidae have been debated, and some authors have concluded they donot belong in Hesionidae. Herein, based on morphological characters, a phylogenetic analysis of the subfamily and some other similar poorly-known genera, with anuncertain position in Hesionidae was performed to clarify their affinities. Our results indicate that Microphthalminae, as currently delimited, is paraphyletic. The inclusion of Struwela, Uncopodarke, and Westheideius, a new genus, as well as the recognition of Fridericiella are proposed to meet the requirement of monophyly; and as result of this, the elevation in rank to the family level is herein presented. Furthermore, the type species for Hesionella and Struwela are redescribed, and a new species in the latter is described. A key to identify microphthalmid genera is also included.


8.
- Artículo con arbitraje
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Re-evaluation of the morphology of the monotypic genera Lycastonereis Rao, 1981 and Ganganereis Misra, 1999 (Annelida, Phyllodocida, Nereididae)
Conde Vela, Víctor Manuel (autor) ;
Disponible en línea
Contenido en: Zootaxa Vol. 4567, no. 3 (Mar. 2019), p. 450-460 ISSN: 1175-5326
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Resumen en: Inglés |
Resumen en inglés

The monotypic genera Lycastonereis Rao, 1981 and Ganganereis Misra, 1999, and their respective species L. indica Rao, 1981 and G. sootai Misra, 1999, have unique morphological traits, and are only known from India and nearby countries. Lycastonereis is diagnosed by having three pairs of anterior cirri and biramous parapodia, whereas for Ganganereis the pharynx has partially sclerotized papillae arranged in a semi-continuous row in the maxillary ring, and chaetae include only spinigers throughout the body. The morphology of these species is not adequately understood as shown by their exclusion in phylogenetic analyses, and therefore an additional morphological evaluation is needed. The re-evaluation of the genera is based upon three specimens of L. indica and the original description of G. sootai. It is shown that L. indica has rounded papillae present in both maxillary and oral rings (not restricted to the oral ring), and in all areas except area V, and neuroacicular ligules are bilobed (not the postchaetal lobes). In addition, G. sootai is morphological similar to species of Paraleonnates Khlebovich & Wu, 1962, mainly in the arrangement and kind of structures of the pharynx, parapodial morphology, and chaetae; therefore, G. sootai is transferred to Paraleonnates, and Ganganereis is regarded as a junior synonym of Paraleonnates. A key to species of Paraleonnates is included.


9.
Artículo
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Use of exochorion characters for the systematics of Hamadryas Hübner and Ectima Doubleday (Nymphalidae: Biblidinae: Ageroniini)
Nieves Uribe, Sandra ; Flores Gallardo, Adrián (coaut.) ; Llorente Bousquets, Jorge E. (coaut.) ; Luis Martínez, Moisés Armando (coaut.) ; Pozo, Carmen (coaut.) ;
Contenido en: Zootaxa Vol. 4619, no. 1 (June 2019), p. 77-108 ISSN: 1175-5326
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Resumen en: Inglés |
Resumen en inglés

We studied the chorionic morphology of six species of Hamadryas, and together with previous studies, we compared our results with previously published phylogenies for the genus. Samples were obtained from 19 females collected between 2013 and 2017 whose abdomens were sectioned and preserved for later dissection. Eggs were extracted from those dissections and used for the descriptions and illustrations of the chorion. The Hamadryas egg is of the globose type; it is quasi-spheroidal and has multiple polygonal grids with differentiation in specific zones/regions, and knolls with macrocells in their summits that arise in the apical third. These characteristics are very different from those found in the majority of Biblidinae and for those reported in the literature for Batesia and Panacea, which belong to the same subtribe as Hamadryas (Ageroniina, now Ageroniini). Chorionic characters support a previously suggested division of the genus (februa, feronia and laodamia groups) and they agree with the phylogenetic proposal based on morphological characters. Our study expands previous morphological work focused on this genus and compiles all the information available to date about the exochorion of Hamadryas, which now includes data for 10 species and that of Ectima thecla thecla, the putative sister group of Hamadryas.


10.
- Artículo con arbitraje
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Worming its way into Patagonia: an integrative approach reveals the cryptic invasion by Eulalia clavigera (Annelida: Phyllodocidae)
Langeneck, Joachim ; Diez, María Emilia (coaut.) ; Nygren, Arne (coaut.) ; Salazar Vallejo, Sergio I. (coaut.) ; Carrera Parra, Luis Fernando (coaut.) ; Vega Fernández, Tomás (coaut.) ; Badalamenti, Fabio (coaut.) ; Castelli, Alberto (coaut.) ; Musco, Luigi (coaut.) ;
Contenido en: Marine Biodiversity Vol. 49, no. 2 (April 2019), p. 851-861 ISSN: 1867-1616
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Resumen en: Inglés |
Resumen en inglés

A phyllodocid polychaete belonging to the genus Eulalia is reported from Nuevo Gulf, Patagonia (South-western Atlantic Ocean) with abundant populations thriving in the intertidal zone. Morphological and molecular data allowed assigning this population to Eulalia clavigera (Audouin & Milne-Edwards, 1834), a species typically occurring along the north-eastern Atlantic coast. The absence of genetic structuring between north-eastern and south-western Atlantic E. clavigera strongly supports a non-native origin of the Patagonian population. Conversely, the majority of the Mediterranean Eulalia cf. clavigera analysed in this study turned out to belong to a different, probably undescribed species, suggesting that the diversity and taxonomy of green Eulalia is more complex than previously supposed. The high adaptation capabilities to stressed environments showed by E. clavigera, along with its possible high impact on native assemblages through predation, compel to carefully monitor its spread along the Patagonian coasts.