Acoustic Communication in Blandford (Curculionidae Scolytinae): Description of Calls and Sound Production Mechanism.

The acoustic communication system (ACS) in bark beetles has been studied mainly in species of the genera , and . Specifically, ACS of the roundheaded pine beetle, , has been little studied. In this study, we described the stridulatory apparatus of this beetle using optical and scanning electron microscopy and recorded the call types produced by males in three behavioral contexts: stress, female-male-, and male-male interactions.

Comparative metabarcoding and biodiversity of gut-associated fungal assemblages of species (Curculionidae: Scolytinae).

The genus is a Holarctic taxon composed of 21 nominal species; some of these species are well known in the world as disturbance agents of forest ecosystems. Under the bark of the host tree, these insects are involved in complex and dynamic associations with phoretic ectosymbiotic and endosymbiotic communities. Unlike filamentous fungi and bacteria, the ecological role of yeasts in the bark beetle holobiont is poorly understood, though yeasts were the first group to be recorded as microbial symbionts of these beetles.

Molecular and morphological data suggest a new species of big-eared bat (Vespertilionidae: Corynorhinus) endemic to northeastern Mexico.

Corynorhinus mexicanus is an insectivorous bat endemic to Mexico that inhabits the high and humid regions of the Sierra Madre Oriental (SMO), the Trans-Mexican Volcanic Belt (TMVB), and the Sierra Madre Occidental (SMOC). A previous study suggested that C. mexicanus could be a cryptic species complex due to the genetic divergence observed between specimens from the TMVB and SMOC.

Dysbiosis by Eradication of Infection Associated with Follicular Gastropathy and Pangastropathy.

Dysbiosis plays an important role in the development of bacterial infections in the gastric mucosa, particularly . The international guidelines for the treatment of infections suggest standard triple therapy (STT). Nevertheless, because of the increasing resistance rates to clarithromycin, metronidazole has been widely considered in several countries.

Metabarcoding of mycetangia from the species complex (Curculionidae: Scolytinae) reveals diverse and functionally redundant fungal assemblages.

-bark beetles are associated with microbes that can detoxify terpenes, degrade complex molecules, supplement and recycle nutrients, fix nitrogen, produce semiochemicals, and regulate ecological interactions between microbes. Females of some species harbor microbes in specialized organs called mycetangia; yet little is known about the microbial diversity contained in these structures. Here, we use metabarcoding to characterize mycetangial fungi from beetle species in the complex, and analyze variation in biodiversity of microbial assemblages between beetle species.

Gut transcriptome of two bark beetle species stimulated with the same kairomones reveals molecular differences in detoxification pathways.

bark beetles are the most destructive agents in coniferous forests. These beetles come into contact with the toxic compounds of their host's chemical defenses throughout their life cycle, some of which are also used by the insects as kairomones to select their host trees during the colonization process. However, little is known about the molecular mechanisms by which the insects counteract the toxicity of these compounds.

Nucleotide substitutions in the mexR, nalC and nalD regulator genes of the MexAB-OprM efflux pump are maintained in Pseudomonas aeruginosa genetic lineages.

Pseudomonas aeruginosa has different resistant mechanisms including the constitutive MexAB-OprM efflux pump. Single nucleotide polymorphisms (SNPs) in the mexR, nalC, and nalD repressors of this efflux pump can contribute to antimicrobial resistance; however, it is unknown whether these changes are mainly related to genetic lineages or environmental pressure. This study identifies SNPs in the mexR, nalC, and nalD genes in clinical and environmental isolates of P.

Role of and Other Environmental Factors in the Development of Gastric Dysbiosis.

Microbiomes are defined as complex microbial communities, which are mainly composed of bacteria, fungi, and viruses residing in diverse regions of the human body. The human stomach consists of a unique and heterogeneous habitat of microbial communities owing to its anatomical and functional characteristics, that allow the optimal growth of characteristic bacteria in this environment. Gastric dysbiosis, which is defined as compositional and functional alterations of the gastric microbiota, can be induced by multiple environmental factors, such as age, diet, multiple antibiotic therapies, proton pump inhibitor abuse, status, among others.

Y chromosome diversity in descendants and its implications for the history of Central Mexico.

Native Mexican populations are crucial for understanding the genetic ancestry of Aztec descendants and coexisting ethnolinguistic groups in the Valley of Mexico and elucidating the population dynamics of the prehistoric colonization of the Americas. Mesoamerican societies were multicultural in nature and also experienced significant admixture during Spanish colonization of the region. Despite these facts, Native Mexican Y chromosome diversity has been greatly understudied.

Evidence for Semiochemical Divergence Between Sibling Bark Beetle Species: Dendroctonus brevicomis and Dendroctonus barberi.

We investigated geographic variation in the semiochemistry of major disturbance agents of western North American pine forests, Dendroctonus brevicomis Le Conte and Dendroctonus barberi Hopkins (Coleoptera: Curculionidae: Scolytinae), species separated by the Great Basin in the USA that until recently were synonymous. At 15 sites in the western USA and northern Mexico, beetle populations were examined to determine (1) pheromone production by solitary, mining females, (2) male electroantennogram amplitudes in response to known semiochemicals for the genus, or (3) relative attractiveness of two female-produced pheromone components (endo- and exo-brevicomin) and two host odors (alpha-pinene and myrcene) to beetles in the field. Compared to female beetles collected east of the Great Basin (D.

Association of Genetic Polymorphisms in , , , and with the Clinical Forms of Dengue in Patients from Veracruz, Mexico.

Dengue manifestations range from a mild form, dengue fever (DF), to more severe forms such as dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). The ability of the host to present one of these clinical forms could be related to polymorphisms located in genes of the Toll-like receptors (TLRs) which activate the pro-inflammatory response. Therefore, the genotyping of single nucleotide genetic polymorphisms (SNPs) in (rs3775291 and rs6552950), (rs2737190, rs10759932, rs4986790, rs4986791, rs11536865, and rs10983755), (rs179008 and rs3853839), and (rs3764880, rs5741883, rs4830805, and rs1548731) was carried out in non-genetically related DHF patients, DF patients, and general population (GP) subjects.

The effect of landscape on functional connectivity and shell shape in the land snail .

The populations of have experienced a drastic reduction in the effective population size; in addition, the species is threatened by anthropogenic activities. For the aforementioned, landscape genetics will serve as a tool to define the potential evolutionarily significant units (ESU) for this species. To complete our objective, we evaluated the effect of cover vegetation and climate on the functional connectivity of the species from the last glacial maximum (LGM) to the present as well as the effect of climate on shell shape.

Seasonal changes in the bacterial community structure of three eutrophicated urban lakes in Mexico city, with emphasis on Microcystis spp.

Artificial urban lakes commonly have physicochemical conditions that contribute to rapid anthropogenic eutrophication and development of cyanobacterial blooms. Microcystis is the dominat genus in most freshwater bodies and is one of the main producter of microcystins. Using 454-pyrosequencing we characterized the bacterial community, with special emphasis on Microcystis, in three recreational urban lakes from Mexico City in both wet and dry seasons.

The role of head shape and trophic variation in the diversification of the genus Herichthys in sympatry and allopatry.

In the present study we evaluated the putative cases of sympatric speciation in the genus Herichthys by studying the variation in head shape using principal component analysis, phylomorphospace and reconstructions of the ancestral states of feeding preferences. Herichthys includes both allopatric and sympatric sister species, as well as sympatric unrelated species and thus offers great potential for evolutionary studies of putatively sympatric speciation. Herichthys is the northernmost group of cichlids in America and one of the most ecologically disparate genera within Middle American cichlids.

Cryptic Species Discrimination in Western Pine Beetle, LeConte (Curculionidae: Scolytinae), Based on Morphological Characters and Geometric Morphometrics.

The western pine beetle (WPB), LeConte, is a major mortality agent of pines in North America. A total of 706 adults of WPB from 81 geographical sites were analyzed with traditional and geometric morphometric methods to evaluate the variation of discrete and quantitative morphological characters with particular attention to the antenna, spermatheca, and seminal rod. Principal coordinates and canonical variate analyses supported three geographical groups in WPB: (1) West, from British Columbia to southern California along the Pacific coast, Idaho, and Montana; (2) East-SMOC, including Nevada, Utah, Colorado, Arizona, New Mexico, Texas, Chihuahua, and Durango; and (3) SMOR, including Coahuila, Nuevo Leon, and Tamaulipas.

An Overview of Genes From , a Symbiont Yeast Isolated From the Gut of the Bark Beetle (Curculionidae: Scolytinae), Involved in the Detoxification Process Using Genome and Transcriptome Data.

Bark beetles from genus promote ecological succession and nutrient cycling in coniferous forests. However, they can trigger outbreaks leading to important economic losses in the forest industry. Conifers have evolved resistance mechanisms that can be toxic to insects but at the same time, bark beetles are capable of overcoming tree barriers and colonize these habitats.

The Differential Expression of Mevalonate Pathway Genes in the Gut of the Bark Beetle (Curculionidae: Scolytinae) Is Unrelated to the de Novo Synthesis of Terpenoid Pheromones.

Bark beetles commonly produce de novo terpenoid pheromones using precursors synthesized through the mevalonate pathway. This process is regulated by Juvenile Hormone III (JH III). In this work, the expression levels of mevalonate pathway genes were quantified after phloem feeding-to induce the endogenous synthesis of JH III-and after the topical application of a JH III solution.

Time-Course of CYP450 Genes Expression From Dendroctonus rhizophagus (Curculionidae: Scolytinae) During Early Hours of Drilling Bark and Settling Into the Host Tree.

Dendroctonus bark beetles (Scolytinae) are one of the most important disturbance agents of coniferous forests in North and Central America. These beetles spend their lives almost entirely under the tree bark, and their survival and reproductive success depend on their ability to overcome the toxic effect of the trees' oleoresin. The cytochromes P450 (CYPs) are associated with the detoxification process of xenobiotics, as well as other physiological processes.

An Assessment of Old and New Characters Using Traditional and Geometric Morphometrics for the Identification of Dendroctonus approximatus and Dendroctonus parallelocollis (Curculionidae: Scolytinae).

There have been numerous changes in the nomenclature of species of Dendroctonus. The case of Dendroctonus parallelocollis Chapuis and Dendroctonus approximatus Dietz has been particularly noteworthy. These bark beetles colonize pine trees but are not aggressive species.