Alejandro Piñeiro-González

Islands provide valuable opportunities to study how isolation affects phenotypic variation. Even though orchid bees are highly mobile, their movement can still be restricted by marine barriers. In this study, we assessed whether insular isolation impacts wing shape in the orchid bee Euglossa mixta across the Coiba archipelago and a nearby mainland site in Western Panama. Our study analyzed 271 individuals using geometric morphometrics, focusing on forewing venation landmarks, and evaluated the variation using multivariate analyses of shape variation and quantifying the shape of Mahalanobis distances. Additionally, we conducted a Mantel test to explore the relationship between geographic distance and morphological divergence. Our findings reveal that wing shape variation in E. mixta is largely conserved but shows fine-scale structuring consistent with spatial patterns expected in insular systems. These results suggest that even highly mobile pollinators may experience enough isolation for subtle phenotypic shifts to occur, highlighting the sensitivity of geometric morphometrics for detecting early stages of morphological differentiation.

The study of shape by the use of geometric morphometrics has been an important tool for addressing taxonomic challenges in complex groups like the genus Tetropium Kirby, 1837 (Coleoptera, Cerambycidae). This insect genus includes 28 species, 8 of which are found in North America, with the invasive T. fuscum (Fabricius) posing a significant quarantine risk as a pest of coniferous trees. The present study evaluated the use of geometric morphometrics to analyze the pronotum shape in females of nine species of the genus, showing the effectiveness of this tool in distinguishing between species. Even if some overlaps were found between some species, this research highlights the potential of GM in developing pest monitoring, quarantine managements, and integrated pest management programs. Our findings suggest that the use of a comprehensive database of landmarks, encompassing broader geographic and ecological diversity, could further improve species identification at ports of entry and facilitate trade.

Se encontró una larva de sapo hermoso Telmatobufo venustus, desplazándose contra la corriente de un río usando su disco oral como ventosa. Esta conducta no ha sido reportada en el género Telmatobufo, pero muestra similitudes morfológicas y conductuales con otros renacuajos con conductas suctoriales y que se desarrollan en sistemas lóticos. Es necesario realizar estudios adicionales para entender la importancia ecológica de esta conducta en una especie categorizada como “En Peligro”, especialmente ante distintas amenazas como la sedimentación de arroyos y la presencia de depredadores invasores.

The Andean Altiplano, characterized by its extreme climatic conditions and high levels of biodiversity, provides a unique environment for studying ecological and evolutionary adaptations in insect morphology. Butterflies, due their large wing surface compared to body surface, and wide distribution among a geographical area given the flight capabilities provided by their wings, constitute a good biological model to study morphological adaptations following extreme weathers. This study focuses on Phulia nymphula, a butterfly species widely distributed in the Andes, to evaluate wing shape variation across six localities in the Northern Chilean Altiplano. The geometric morphometrics analysis of 77 specimens from six locations from the Chilean Altiplano (Caquena, Sorapata Lake, Chungará, Casiri Macho Lake, Surire Salt Flat, and Visviri) revealed significant differences in wing shape among populations. According to the presented results, variations are likely influenced by local environmental conditions and selective pressures, suggesting specific adaptations to the microhabitats of the Altiplano. The first three principal components represented 60.92% of the total wing shape variation. The detected morphological differences indicate adaptive divergence among populations, reflecting evolutionary responses to the extreme and fragmented conditions of the Altiplano. This study gives insights into the understanding of how high-altitude species can diversify and adapt through morphological variation, providing evidence of ecological and evolutionary processes shaping biodiversity in extreme environments.