Validation, application, and practical use of the origami-based Foldscope microscope for biomonitoring soil and litter arthropods

The purpose of this study was to evaluate the potential of the origami-based Foldscope microscope, supplemented with smartphone cameras, as a practical, affordable, and field-ready tool for monitoring soil and litter arthropod diversity in tropical forest ecosystems of Mizoram, India (Aizawl, Lunglei, and Mamit). We surveyed arthropod diversity across multiple taxa—including Protura, Diplura, Collembola, Orthoptera, Coleoptera, Hymenoptera, Diptera, Araneae, and others—and compared image quality with conventional student microscopes. We hypothesized that the Foldscope, when coupled with smartphone imaging, would generate diagnostically useful images of soil and litter arthropods comparable to those obtained with conventional microscopes, thereby serving as a practical tool for biodiversity monitoring in field conditions. To test this, our objectives were: (i) to survey soil and litter arthropod diversity in three tropical forest regions using Foldscope; (ii) to compare its imaging performance with conventional microscopes; and (iii) to examine the broader implications of low-cost, field-based microscopy for biodiversity monitoring and scientific equity. Our results demonstrate that the Foldscope reliably produced diagnostically useful images of key soil and litter arthropod groups under natural field conditions, underscoring its utility as a low-cost, portable alternative to conventional laboratory instruments. Beyond documenting biodiversity patterns, this study highlights the role of accessible instrumentation in advancing ecological research and education. In resource-constrained contexts, the scarcity of laboratory-grade microscopes often limits opportunities for field-based inquiry. By enabling in situ collection and analysis, the Foldscope lowers barriers to participation in biodiversity monitoring, environmental education, and citizen science. We further argue that this work underscores the responsibility of instrument developers to address the needs of under-resourced scientific communities. Foldscope’s adoption, compared with other open-source platforms such as UC2 and OpenFlexure, illustrates the importance of intuitive design, compatibility with digital tools, and potential integration with open-source artificial intelligence for image analysis. By presenting this work as both a validation study and a perspective from a resource-limited research setting, we establish Foldscope not only as a validated tool for ecological monitoring but also as a model of how affordable instruments can strengthen resource-limited research, bridge global inequities, and expand participation in biodiversity science.