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Pseudoeurycea nigromaculata
Number of Pages: 2Integrative BiologyGeological Science
A new species of Craugastor (Anura: Craugastoridae) from the montane rainforest of the Cordillera de Talamanca, Costa Rica
A new species of Craugastor (Anura: Craugastoridae) from the montane rainforest of the Cordillera de Talamanca, Costa Rica. A new dirt frog of the Craugastor podiciferus Species Group is described from Costa Rica; it is restricted to elevations between 2330 and 2700 m a.s.l. in the montane rainforest of the Cordillera de Talamanca. Analysis of DNA sequences of the mitochondrial 16S rRNA (16S) and cytochrome oxidase I (COI) genes reveals a distinct lineage within the C. podiciferus Species Group. Additional morphological and morphometric analyses support the distinctiveness of this lineage that is described as a new species herein. The species is distinguished from other members of the C. podiciferus Species Group by its unique coloration: a violet-brown to blackish brown venter with white pigment forming blotches, and dark brown palmar surfaces with prominent white folds between subarticular tubercles in the adults. The genetic divergence of the species from other members of the C. podiciferus Species Group is signifcant (higher than 9.2% in 16S and 13.3% in COI). Although not closely related, it resembles C. podiciferus morphologically, a species that also inhabits montane rainforest. The discovery of this new species highlights the importance of montane rainforest as a center of species richness and endemism.Uma nova espĂ©cie de Craugastor (Anura: Craugastoridae) do bosque montano chuvoso da Cordilheira de Talamanca, Costa Rica. Descrevemos aqui uma nova espĂ©cie do grupo de Craugastor podiciferus para a Costa Rica, restrita a altitudes entre 2330–2700 m acima do nĂvel do mar no bosque montano chuvoso da Cordilheira de Talamanca. Análises das sequĂŞncias de DNA dos genes mitocondriais16S ARNr (16S) e da citocromo oxidase 1 (COI) revelaram uma linhagem distinta dentro do grupo de espĂ©cies de C. podiciferus. Análises morfolĂłgicas e morfomĂ©tricas complementares apoiaram a diferenciação desta linhagem, que descrevemos aqui como uma espĂ©cie nova. Essa espĂ©cie distingue-se dos membros do grupo de espĂ©cies de C. podiciferus por sua coloração Ăşnica: ventre marrom-violeta a marrom enegrecido com pigmento branco formando manchas e superfĂcie palmar nos adultos marrom escura com pregas brancas proeminentes entre os tubĂ©rculos sub-articulares. Geneticamente esta nova espĂ©cie Ă© signifcativamente divergente dos demais membros do grupo de espĂ©cies de C. podiciferus (maiores em 9.3% no 16S e 13.3% no COI). Ainda que nĂŁo estejam estreitamente relacionadas, a nova espĂ©cie Ă© morfologicamente similar a C. podiciferus, que tambĂ©m habita o bosque montano chuvoso. A descoberta dessa nova espĂ©cie ressalta a importância do bosque montano chuvoso como um centro de riqueza de espĂ©cies e endemismos.Una especie nueva de Craugastor (Anura: Craugastoridae) del bosque montano lluvioso en la Cordillera de Talamanca, Costa Rica. Se describe una especie nueva para Costa Rica de rana de hojarasca perteneciente al grupo de especies Craugastor podiciferus, restringida a elevaciones entre 2330–2700 m s.n.m. en el bosque montano lluvioso de la Cordillera de Talamanca. Análisis de las secuencias del ADN de los genes mitocondriales 16S ARNr (16S) y citocromo oxidasa 1 (COI) revelĂł un linaje distinto dentro del grupo de especies C. podiciferus. Los análisis complementarios de morfologĂa y morfometrĂa apoyaron la diferenciaciĂłn de este linaje, el cual describimos aquĂ como una especie nueva. Esta especie se distingue de los miembros del grupo de especies C. podiciferus por su coloraciĂłn Ăşnica: vientre violeta-marrĂłn a marrĂłn negruzco con pigmento blanco formando manchas, la superfcie palmar en adultos es marrĂłn oscuro con pliegues blancos prominentes entre los tubĂ©rculos subarticulares. Geneticamente esta nueva especie es signifcativamente divergente de los demás miembros del grupo de especies C. podiciferus (mayores a 9.3% en el 16S y 13.3% en COI). Aunque no están estrechamente relacionadas, la nueva especie es morfolĂłgicamente similar a C. podiciferus, especie que tambiĂ©n habita en el bosque montano lluvioso. El descubrimiento de esta nueva especie resalta la importancia del bosque montano lluvioso como un centro de riqueza de especies y endemismos
Distribution of Verodes aequalis (Coleoptera: Zopheridae), a Poorly Known Species from Cloud Forests of Mexico
Verodes aequalis (Champion) was previously known only from its type locality (“Parada, Mexico”, likely close to Cerro San Felipe, Oaxaca, Mexico). We provide several new localities from the mountains of northern Oaxaca and neighboring Veracruz representing a major range extension. All specimens were captured in pine and pine-oak forests in the cloud zone above 2130 m asl.Peer reviewe
Batrachochytrium salamandrivorans’ Amphibian Host Species and Invasion Range
Batrachochytrium salamandrivorans (Bsal), a species related to the destructive pathogen Batrachochytrium dendrobatidis (Bd), was found and identified in Europe in 2013. Now, a decade later, a large amount of information is available. This includes data from studies in the field, reports of infection in captive amphibians, laboratory studies testing host susceptibility, and data from prospective studies that test for Bsal’s presence in a location. We conducted a systematic review of the published literature and compiled a dataset of Bsal tests. We identified 67 species that have been reported positive for Bsal, 20 of which have a threatened conservation status. The distribution of species that have been found with infection encompasses 69 countries, highlighting the potential threat that Bsal poses. We point out where surveillance to detect Bsal have taken place and highlight areas that have not been well monitored. The large number of host species belonging to the families Plethodontidae and Salamandridae suggests a taxonomic pattern of susceptibility. Our results provide insight into the risk posed by Bsal and identifies vulnerable species and areas where surveillance is needed to fill existing knowledge gaps
Amphibians and reptiles from cloud forest at Cumbre de Tonalixco in the central Veracruz highlands of Mexico
The role of Central American barriers in shaping the evolutionary history of the northernmost glassfrog, Hyalinobatrachium fleischmanni (Anura: Centrolenidae)
The complex geological history of Central America has been useful for understanding the processes influencing the distribution and diversity of multiple groups of organisms. Anurans are an excellent choice for such studies because they typically exhibit site fidelity and reduced movement. The objective of this work was to identify the impact of recognized geographic barriers on the genetic structure, phylogeographic patterns and divergence times of a wide-ranging amphibian species, Hyalinobatrachium fleischmanni. We amplified three mitochondrial regions, two coding (COI and ND1) and one ribosomal (16S), in samples collected from the coasts of Veracruz and Guerrero in Mexico to the humid forests of Chocó in Ecuador. We examined the biogeographic history of the species through spatial clustering analyses (Geneland and sPCA), Bayesian and maximum likelihood reconstructions, and spatiotemporal diffusion analysis. Our data suggest a Central American origin of H. fleischmanni and two posterior independent dispersals towards North and South American regions. The first clade comprises individuals from Colombia, Ecuador, Panama and the sister species Hyalinobatrachium tatayoi; this clade shows little structure, despite the presence of the Andes mountain range and the long distances between sampling sites. The second clade consists of individuals from Costa Rica, Nicaragua, and eastern Honduras with no apparent structure. The third clade includes individuals from western Honduras, Guatemala, and Mexico and displays deep population structure. Herein, we synthesize the impact of known geographic areas that act as barriers to glassfrog dispersal and demonstrated their effect of differentiating H. fleischmanni into three markedly isolated clades. The observed genetic structure is associated with an initial dispersal event from Central America followed by vicariance that likely occurred during the Pliocene. The southern samples are characterized by a very recent population expansion, likely related to sea-level and climatic oscillations during the Pleistocene, whereas the structure of the northern clade has probably been driven by dispersal through the Isthmus of Tehuantepec and isolation by the Motagua–Polochic–Jocotán fault system and the Mexican highlands
New occurrence records of Eleutherodactylus syristes in Guerrero and Oaxaca, Mexico
AbstractThe Sierra Madre del Sur (SMS) of southern Mexico is known for its exceptionally high levels of amphibian endemism, but knowledge of species’ ranges in the region is incomplete. Here, we report new locality records for Eleutherodactylus syristes (Hoyt, 1965) from the states of Oaxaca and Guerrero. Previously, this species was known only from the Pacific slopes of the Sierra de Miahuatlán and Mixteca Alta in Oaxaca. These new occurrence records extend the known range of this species by approximately 335km from the type locality and increase the elevational range, indicating it is more widespread in the SMS. Eleutherodactylus syristes is currently listed as endangered by the IUCN based on its limited distribution and ongoing threats to its persistence
Complex history of the amphibian-killing chytrid fungus revealed with genome resequencing data
Understanding the evolutionary history of microbial pathogens is critical for mitigating the impacts of emerging infectious diseases on economically and ecologically important host species. We used a genome resequencing approach to resolve the evolutionary history of an important microbial pathogen, the chytrid Batrachochytrium dendrobatidis (Bd), which has been implicated in amphibian declines worldwide. We sequenced the genomes of 29 isolates of Bd from around the world, with an emphasis on North, Central, and South America because of the devastating effect that Bd has had on amphibian populations in the New World. We found a substantial amount of evolutionary complexity in Bd with deep phylogenetic diversity that predates observed global amphibian declines. By investigating the entire genome, we found that even the most recently evolved Bd clade (termed the global panzootic lineage) contained more genetic variation than previously reported. We also found dramatic differences among isolates and among genomic regions in chromosomal copy number and patterns of heterozygosity, suggesting complex and heterogeneous genome dynamics. Finally, we report evidence for selection acting on the Bd genome, supporting the hypothesis that protease genes are important in evolutionary transitions in this group. Bd is considered an emerging pathogen because of its recent effects on amphibians, but our data indicate that it has a complex evolutionary history that predates recent disease outbreaks. Therefore, it is important to consider the contemporary effects of Bd in a broader evolutionary context and identify specific mechanisms that may have led to shifts in virulence in this system.Instituto de Botánica "Dr. Carlos Spegazzini
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