Jake Lewis, an entomologist at OIST, is passionate about weevils, a group of beetles known for their elephant trunk-like mouthparts. Weevils play important roles in ecosystems, but some species can be destructive pests. Using x-ray microtomography, Lewis and his team identified 12 new weevil species from Japan, Malaysia, Vietnam, and Taiwan, ranging in size from 1.5 to 3.0 mm. This technique allowed them to remove scales covering the cuticle of the weevils and examine underlying morphological differences for taxonomic purposes.
The researchers found that x-ray microtomography revealed significant morphological differences between species that were not easily observable with other methods. This technique may become more popular for identifying new insect species, especially those covered in scales or debris. Lewis examined specimens from various collections worldwide to study the poorly understood genus Aphanerostethus. Through traditional methods such as light microscopy, dissections, and DNA barcoding, they were able to differentiate between species and create a phylogenetic tree.
In addition to traditional methods, x-ray microtomography was used to examine the structure of the hidden cuticle and hindwings of the weevils. Aphanerostethus weevils have lost the ability to fly due to the gradual reduction of their hindwings, and this reduction varied between species. The varying degrees of hindwing loss provide insight into the ongoing process of evolutionary change within these insects. X-ray microtomography is valuable for studying internal anatomy without damaging rare specimens that cannot be dissected.
Discovering new weevil species can be challenging due to their diversity and specialization. Some species are highly host-specific, occupy specific microhabitats, and have limited adult lifespans. Protecting and investing in specimen collections is crucial for documenting biodiversity changes and understanding ecosystems. Specimen collections are essential tools for scientific research and conservation biology, helping to preserve vital information on species and ecosystems before they are lost.
The new weevil species discovered in Japan are part of the country’s natural heritage and contribute to a greater understanding of its biodiversity. Protected areas like Yanbaru National Park, where one of the new species was found, are vital for safeguarding Japan’s unique and endemic wildlife. Investigating new species and documenting their biology is essential for conservation efforts and to ensure the protection of Japan’s rich natural habitats and ecosystems. Investing in specimen collections and supporting the people who maintain them is crucial for preserving valuable information on species diversity and environmental changes.
