This study investigates the dynamic, time-varying associations between multiple socio-ecological stressors and internalizing symptoms among Mexican-origin youth from low-income immigrant families. Grounded in a socioecological framework and employing time-varying effect modeling (TVEM), we examine how stressors at the interpersonal, family, and neighborhood levels differentially influence anxiety and depressive symptoms across early adolescence (ages 11–13), middle adolescence (ages 14–17), and late adolescence/emerging adulthood (ages 18–20). Participants included 604 Mexican-origin adolescents (54% female) from low-income immigrant families, assessed across three waves spanning nine years. Five distinct stressors were identified: discrimination, foreigner stress, economic stress, language brokering stress, and neighborhood violence/non-safety. Results from TVEM analyses revealed that the impact of discrimination on internalizing symptoms was more pronounced during early and middle adolescence, while foreigner stress became increasingly more pronounced in late adolescence/emerging adulthood. Economic hardship and language brokering stress consistently predicted internalizing symptoms across all developmental periods, whereas neighborhood violence/non-safety exerted the greatest influence during early adolescence. These findings underscore the importance of considering how stressor type and developmental timing intersect to shape mental health outcomes. Moreover, the results suggest that identifying sensitive windows for specific socio-ecological stressors can inform the optimal timing of tailored, developmentally sensitive interventions to mitigate their adverse effects.

The habitat use and the phenology of the large grasshopper Acrostira euphorbiae García & Oromí endemic to La Palma (Canary Islands) are studied. This grasshopper is entirely dependent on the Canarian endemic shrub Euphorbia lamarckii both for food and to avoid predation. Adults stay on subapical branches during the day, probably to reduce the risk of predation, and climb up to the apex at night to feed. While females seem to ensure the genetic diversity of offspring by waiting for visits by different males, the latter have to move to guarantee their reproductive success. Monophagy in this species may be related to the year-round presence of tender shoots, and to the predator-repellent toxic latex found in the host plant. Unlike related species from continental areas, adults and nymphs of A. euphorbiae are present almost all year round, probably in adaptation to the particular climate of the islands. Nymphs are more abundant in winter, when Euphorbia leaves are most available. However, adults are more abundant than nymphs in spring, summer and autumn. Males develop more quickly than females, an apparent reproductive strategy based on achieving sexual maturity to coincide with females undergoing imaginal moulting. Matings start immediately after adult females emerge. Densities oscillated between 73 and 193 individuals ha−1, which can be considered a low value compared with other continental pamphagid species.

A system for developmental timing for Panstrongylus megistus and Rhodnius prolixus (Hemiptera: Reduviidae) adults is presented, using as a marker, the evolution of the cuticular tanning after ecdysis. In both species the setting of the cuticular pigmentation pattern after imaginal moult is a homogeneous process in population, i.e. no individual variations were detected. The system allows one to estimate the exuvial time up to 5 or 7 hr after occurrence. A preferential exuvial period (PEP) was determined in the population under usual rearing conditions by using this system. The PEP runs from 2100 to 0500 hr for P. megistus and from 0100 to 0800 hr for R. prolixus. These data are meaningful for endocrine studies on those species. Studies on PEP under natural environmental conditions would be useful for the control of Chagas' disease vectors.