◆Research findings by a group led by Professor Kei Ito of the Department of Life, Environmental, and Medical Sciences in the School of Integrated Sciences have been published in the Dutch journal *Entomologia Experimentalis et Applicata*
Release Date:
Study reveals that social mites work together to ward off predators
~ "Neighborhood Patrols" Triggered by Stimulation of the Nest Web ~
A research group led by Professor Kei Ito of the Department of Life and Environmental Medicine in the Faculty of Integrated Sciences at Kochi University, along with alumni Maiko Chida and Tomohiro Mizuguchi from the Faculty of Agriculture, Forestry, and Marine Sciences, has revealed that Schizotetranychus brevisetosus, a mite that parasitizes the evergreen broadleaf tree Quercus acutissima, actively engages in defensive behavior against predators, and that this behavior is triggered by physical stimulation.
The oak leaf mite, which parasitizes the Japanese oak, forms a web and lives inside it. When tiny glass beads are sprinkled onto the web of this mite, many adult females emerge from the web and begin patrolling; upon finding the eggs of predatory mites placed around the web, they exhibit aggressive behavior by piercing and killing them with their mouthparts.
Such behavior has never been reported in mites before and is believed to be a social behavior that evolved independently over time.
Furthermore, some spider mites are notorious as agricultural pests that are difficult to control. Until now, little attention has been paid to how the “behavior induced by physical stimulation” revealed in this study affects reproduction. While we observed “counterattacks against predators” in this study, the associated loss of reproductive capacity (cost) remains unclear. If physical stimulation reduces the reproductive capacity of spider mites, it could potentially aid in their control as agricultural pests.
These findings were published on May 10, 2025, in the international entomology journal *Entomologia Experimentalis et Applicata* (Journal of the Entomological Society of the Netherlands).
[Paper Information]
Title: Evaluation of the effectiveness of counterattacks against predators in Schizotetranychus brevisetosus using small glass beads and phytoseiid eggs
Authors: Maiko Chida, Tomohiro Mizuguchi, Katsura Ito
Affiliation: Faculty of Agriculture, Forestry and Marine Sciences, Kochi University
Journal Title: Entomologia Experimentalis et Applicata
DOI: 10.1111/eea.13590
Published: May 10, 2025