Researchers have officially identified a new species of subterranean termite in Southern California. For decades, it was believed that only two species in the Reticulitermes genus existed in California. These were Reticulitermes hesperus, a well-known pest responsible for significant structural damage, and Reticulitermes tibialis, which is more commonly found in arid environments. However, a 2023 study led by Chow Yang Lee, the endowed presidential chair in urban entomology at the University of California, Riverside, suggested that more species might be present and that Southern California could host an additional, previously undescribed species.
The research team, led by doctoral student Joanne Chen in Lee’s laboratory and joined by scientists from UC Riverside, the U.S. Forest Service, National Taiwan University, and UC Agriculture and Natural Resources, officially identified the new species and named it Reticulitermes rusti.
The name honors retired UC Riverside professor Michael K. Rust, who has contributed extensively to the study of termite biology and management for half a century.
Although researchers cannot determine the exact time when the species diverged, historical records from 1920 show termite swarming events occurring in both spring and fall, indicating that R. rusti has existed for over a century without official recognition. The researchers emphasize that future studies should investigate the ecological roles, behavioral differences, and structural damage potential of both R. hesperus and R. rusti. This is especially important because differences in feeding behavior, colony structure, dispersal methods, and treatment responses can influence the success of control strategies.
In urban environments where termites cause significant economic damage, identifying species level is more than just academic. It directly influences monitoring accuracy, treatment choices, the reliability of baiting systems, and the ability to predict infestation risks. Confirming R. rusti thus represents a major advancement in both entomological science and practical pest management in Southern California.