Temperature Preference of Two Invasive Subterranean Termite Species and Their Hybrids (Blattodea: Rhinotermitidae: Coptotermes)

Temperature preference of two invasive subterranean termites, Coptotermes gestroi (Wasmann) and Coptotermes formosanus Shiraki (Blattodea: Rhinotermitidae), and their hybrids were determined in a horizontal thermal gradient. The activity of workers of four mating combinations: ♀C. gestroi × ♂C. gestroi (C. gestroi), ♀C. formosanus × ♂C. formosanus (C. formosanus), ♀C. gestroi × ♂C. formosanus (Hybrid G), and ♀C. formosanus × ♂C. gestroi (Hybrid F), when placed on the temperature gradients were videotaped and analyzed to determine the mean temperature preference values (mTPV). The temperature ranges for active termites were 21.9–39.5°C for C. gestroi, 11.1–39.5°C for C. formosanus, 25.3–38.2°C for Hybrid G, and 24.9–39.3°C for Hybrid F. There was no significant difference in the mTPV of C. gestroi and both hybrid mating combinations. The mTPV of both Hybrid G and Hybrid F was significantly higher than the parental species C. formosanus. Our results indicate that hybrid populations of C. formosanus and C. gestroi might be more active in tropical than temperate regions, and if established in temperate regions, they will be more active in summer months when the mean temperature exceeds 25°C.