Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

La infección por la bacteria endosimbiótica Wolbachia (Ehrlichiaceae) se ha registrado en una amplia variedad de artrópodos, incluyendo arañas. Dentro del orden Araneae, existen reportes previos de infección por Wolbachia en arañas Synspermiata. En este trabajo, evaluamos la presencia de Wolbachia en los géneros Physocyclus (Pholcidae) y Loxosceles (Sicariidae) mediante estudios moleculares utilizando el marcador mitocondrial Citocromo c oxidasa 1 (CO1). Detectamos la presencia de esta bacteria en una especie de Physocyclus y en siete especies de Loxosceles de México. Nuestros hallazgos representan el quinto registro para la familia Pholcidae y los primeros registros para la familia Sicariidae siendo los primeros registros de la bacteria Wolbachia en arañas de México. Combinando estos resultados con trabajos previos, la infección por Wolbachia en arañas se ha registrado en 19 familias, 70 géneros y 122 especies. La familia Linyphiidae tiene el mayor número de especies reportadas con infecciones por Wolbachia, con 43 especies en 27 géneros. Dentro del clado Synspermiata, Wolbachia ha sido documentada en las familias: Dysderidae, Pholcidae, Telemidae, y Sicariidae, siendo esta última la que tiene la mayoría de los registros con siete especies.

Las abejas sin aguijón desempeñan un importante papel ecológico y económico como polinizadores, especialmente en las regiones tropicales y subtropicales. Sin embargo, algunas especies exhiben un comportamiento cleptobiótico, lo que representa una amenaza para las colonias manejadas y silvestres. El género Lestrimelitta comprende un grupo de abejas sin aguijón que dependen de los recursos obtenidos al invadir otras colonias de abejas. Este estudio reporta a Lestrimelitta niitkib Ayala 1999 (Hymenoptera: Apidae), como una especie que saquea las colmenas de Scaptotrigona mexicana (Guérin-Meneville 1845) y S. pectoralis (Dalla Torre 1896) en Cerro Mirador, Oaxaca. La identificación de L. niitkib se realizó mediante caracterización morfológica y secuenciación del gen mitocondrial citocromo oxidasa 1 (COI). Este hallazgo es significativo debido a que L. niitkib no solo invade, sino que también elimina a las abejas de las colonias que ataca, provocando la destrucción de 20 colmenas manejadas por un meliponicultor local.

Lontra annectens (Neotropical otter) is present in a variety of bodies of water. Its population abundance varies throughout their distribution and is associated with physical-environmental characteristics, including anthropogenic activity. This study provides information on the population size of L. annectens in the Tehuantepec River, Oaxaca, and the possible use of drainage structures as otter passages, before the construction of the Mitla-Tehuantepec highway. 49.3 km of the Tehuantepec River were searched for traces in 2013. 678 records were obtained in 246 km traveled: 511 scats, 76 latrines, 79 footprints, 10 burrows, and 1 sighting. The relative abundance varied from 0.83 to 5.74 records/km traveled, but without significant differences. The number of otters varied from 0.004 to 0.03 otters/km for the Gallo index and from 0.33 to 2.93 otters/km for the Eberhardt and Etten index. Of the 316 drainage structures within the highway section, 117 (37%) had at least one trace within a 0.5 km radius. The estimate of the population size of L. annectens in the Tehuantepec River is among the highest previously recorded for the region. The coincidence between the tracks and the drainage structures can be a sign of possible use by the species, given the lack of passes designed on the Mitla-Tehuantepec highway.  

Alloparental behavior is the care provided to an infant by members of the same species without being the biological parents, it includes allomaternal and allopaternal behavior. Oxytocin (OT) and its receptor (OTR) are involved in the regulation of maternal behavior; OT fibers and its receptor are present in the medial preoptic area (mPOA), the bed nucleus of stria terminalis (BNST), the medial amygdala (MeA), and olfactory bulb (OB), nuclei that regulate maternal behavior. OT and OTR play a significant role in regulating maternal behavior. However, the role of OT and OTR in the regulation of allomaternal behavior has not been established. The aim of this study was to determine whether allomaternal behavior in the Mongolian gerbil is associated with high plasma OT concentrations and the presence of OTR in mPOA, BNST, MeA, and OB. Through exposures to the pups of same species, 10 allomaternal females and 10 aggressive females with the pups were selected. Between 15 and 20 days later, allomaternal behavior tests were performed. Blood samples were then collected to quantify plasma OT concentrations by ELISA. Brains were obtained for OTR immunohistochemistry. The display of allomaternal behavior was associated with high peripheral concentrations of OT and the significant presence of OTR in mPOA/BNST. These results suggest the involvement of OT and OTR in the regulation of the allomaternal behavior of the Mongolian gerbil.

The Sierra de Santa Catarina, located east of Mexico City, is one of the green areas that represent the grasslands and xerophytic scrub in this state. Although the Sierra de Santa Catarina is a state nature reserve, it lacks an up-to-date inventory of its flora and fauna. This study provides information on the bird species present in the three volcanoes (Tetlamanche, Tecuatzin and Mazatepec) out of a total of seven that make up the Sierra, which is the best-preserved area. March 2022 to February 2023, we conducted monthly surveys using the point count method at 11 points, where we recorded the species richness and abundance of the observed taxa. Rarefaction curves were used to assess the completeness of the inventory and range-abundance curves to analyze the dominance of species. We calculated alpha diversity for each month using the Shannon-Wiener index and beta diversity between the two vegetation types. We recorded a total of 113 bird species for the Sierra de Santa Catarina: 96 species observed during the field observations and 17 species recorded in the database, belonging to 11 orders and 29 families. Eight of the recorded species belong to one of the NOM-059 risk categories and 19 show some degree of endemism. According to the rarefaction/extrapolation curve, the inventory is still incomplete. The alpha diversity of the avifauna was H' = 3.22, while H' per month was always >2 (2-3.50). In summary, this site serves as a refuge and feeding ground for at least 113 bird species in Mexico City. Although the results show a greater species diversity than previously observed, a greater sampling effort is required.

A taxonomic key for the determination of the genera and subgenera of dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) for Venezuela is presented in Spanish and English. It includes 42 genera and 29 subgenera for Venezuela, some of which have a geographical distribution close to the Venezuelan territory and are therefore included as far as possible for the country. In addition, photographs of the most relevant structures of external morphology necessary for the correct determination of the Scarabaeinae and a list of 144 species and 10 subspecies with confirmed distribution for the country are presented. This tool aims to contribute to the knowledge and development of new studies of dung beetles in Venezuelan territory, one of the countries with the least studies in this group.

Valencia orange production is affected by Diaphorina citri Kuwayama, 1908 in the Concá Valley, Arroyo Seco, Querétaro, Mexico. To better understand this problem, the temporal abundance of D. citri was determined and correlated with climatic variables in the crop. The study was carried out between 2019 and 2022. To monitor D. citri adults, 20 yellow sticky traps were used per orchard, which were replaced, and the number of adults was recorded every 14 days. D. citri adult counts were carried out in the CIDAF-UAQ Natural Resources Management and Conservation laboratory. Climatic variables were recorded in each orchard using a Hobbo Data Logger. The means of captured adults were analyzed with the Shapiro-Wilk normality test, then the nonparametric Kruskal-Wallis test was applied, additionally a generalized linear mixed model was performed. The spatial autocorrelation of abundance in the orchards was carried out using the Morán index to observe the relationship between abundance and climatic factors the Kernel distribution and a cross-correlation analysis were performed. All statistical analyses were performed in R software, version 4.3.1. The results confirmed the presence of D. citri in the Concá Valley during the four years of the study. There was no consistent population fluctuation pattern each year, the distribution of insects in the orchards is random, with significant differences between them, the abundance of D citri is variable in time scale and a correlation was observed between climatic factors, especially with temperature and wind speed. The importance of considering microclimatic factors of the site to apply more effective management plans for D. citri is highlighted.

In arid ecosystems, where water is scarce and localized, permanent waterholes are critical resources that concentrate the activity of terrestrial vertebrates and may intensify interactions among carnivores. However, little is known about how these guilds structure their coexistence around such sites under seasonally variable conditions. In this study, we analyzed the temporal and spatial use of waterholes by five species of medium- and small-sized carnivores (coyote, bobcat, gray fox, skunk, and raccoon) in an arid ecosystem in northwestern Mexico over two years. Nine camera traps recorded 4,060 detections across 5,931 trap-nights. We estimated daily visitation frequency, daily activity patterns, temporal overlap, and spatial co-occurrence among species throughout the year and between dry and rainy seasons, as well as their relationship with body size differences between speices. Coyotes, bobcats, and foxes increased their visitation rates during the dry season, while skunks maintained and raccoons reduced their visits. Species grouped into two main activity periods: crepuscular (coyote and bobcat) and nocturnal (fox, skunk, and raccoon), with high overlap within groups and moderate overlap between them. No significant seasonal changes were detected in activity patterns. Spatial co-occurrence was lower than expected in both seasons, indicating active avoidance of simultaneous use of waterholes. Body size differences were negatively related to temporal overlap only during the rainy season and showed no association with spatial avoidence. These patterns suggest that carnivore coexistence in arid environments is sustained through behavioral adjustments that minimize direct encounters. Temporal and spatial partitioning function as complementary mechanisms to reduce conflict over critical water resources.

We included the presence of Culex lactator, Cx. apicalis, and Toxorhynchites rutilus septentrionalis in Nuevo León. With the addition of the new records for the state, mosquito diversity rises to 72 species, with the genus Aedes with 22 species and Culex with 18 species, the most diverse in Nuevo León.

Datos digitalizados de diferentes colecciones y la información proveniente de literatura fue analizada para documentar la diversidad de mutílidos de Mexico. Se generó una lista anotada de 369 especies. Este trabajo ha contribuido a incrementar la riqueza de especies conocida para México en un 40.30%. El género con mayor número de especies es Dasymutilla con 114 y los géneros menos diversos son Hoplognathoca, Myrmosula y Pertyella con una especie cada uno. Los estados con el mayor número de géneros son Sonora, Chihuahua y Coahuila y aquellos con el mayor número de especies son Sonora, Baja California y Chihuahua. Este trabajo representa el primer intento de integración de la información sobre la distribución geográfica de los mutílidos de Mexico por estado.