Long-term monitoring data on Popilliajaponica (Newman, 1838) (Coleoptera, Rutelidae) across the Azorean Islands.

Background: The Japanese Beetle, Popilliajaponica Newman, 1838 (Coleoptera, Rutelidae), is a univoltine agricultural pest that poses a serious threat to various agricultural crops. For more than 16 years, the Azorean official authorities have implemented a Long-Term Ecological Research (LTER) programme that is crucial for understanding the dynamics of insect pests, such as the Japanese Beetle, and their impacts on agricultural ecosystems. The significance of this long-term monitoring extends beyond understanding the pest's life cycle. By sharing this long-term monitoring data with the scientific community, we hope it allows for a more comprehensive assessment of P.japonica success and spread, enabling a deeper understanding of how this pest interacts and correlates with biotic and abiotic factors to uncover patterns and trends crucial for effective pest management.In the Azores Archipelago, P.japonica adults emerge from pupae at the end of May and peak in density by early July, persisting until October. Larvae develop through three instars, with the third instar grub pupating by early May. This lifecycle highlights the pest population's seasonal activity, including the timing of emergence, adult stages and larval stages. It reveals when and for how long the pest is active in each of its life stages and provides critical information for pest management strategies. Worldwide, this pest can cause damage to 414 plant species across 94 families, underscoring the potential for elevated crop damage. This information is invaluable for developing targeted intervention strategies and mitigating economic losses caused by P.japonica infestations. Therefore, establishing and maintaining long-term programmes for monitoring P.japonica populations are essential for scientific understanding and practical pest management efforts in the Azores Archipelago.

New information: The data presented here report the officials' records of a 16-year (from 2008 to 2023) long-term monitoring programme on P.japonica in the Azores Archipelago, undertaken by the Secretaria Regional da Agricultura e Alimentação operational services. Based on the last checklist of Azorean arthropods, the species is recorded for the first time for the Corvo, Graciosa and São Jorge Islands.