Densities of adult Aulonium ruficorne Olivier were significantly higher when the beetle prey, Orthotomicus erosus (Wollaston), were in the first two instars. Under controlled conditions, adult longevity was 33.5 d. Female A. ruficorne were more abundant during bark beetle colonization and, later, during the bark beetles' larval stage. However, males outnumbered females during bark beetle oviposition. Eggs were laid under bark scales, in crevices, and in bark beetle frass. The egg distribution was mainly a function of the bark scale distribution and was independent of distance from egg tunnels. There are four or five larval instars. The thermal constant of A. ruficorne is 571 degree-days (lower temperature threshold, 11.3°C). The predator can feed on all immature stages of the bark beetles O. erosus and Pityogenes calcaratus Eichhoff. However, larvae and adults were recorded gnawing bark, and wood particles were observed inside the alimentary canal. In simulated pine tree systems, adults consumed 0.6–1.9 bark beetle eggs or neonates. The combined effect of adults and larvae suggest that this predator might reduce the population of the bark beetles by up to 90% during spring and autumn and by 30–50% during summer.
Densities of adult Aulonium ruficorne Olivier were significantly higher when the beetle prey, Orthotomicus erosus (Wollaston), were in the first two instars. Under controlled conditions, adult longevity was 33.5 d. Female A. ruficorne were more abundant during bark beetle colonization and, later, during the bark beetles' larval stage. However, males outnumbered females during bark beetle oviposition. Eggs were laid under bark scales, in crevices, and in bark beetle frass. The egg distribution was mainly a function of the bark scale distribution and was independent of distance from egg tunnels. There are four or five larval instars. The thermal constant of A. ruficorne is 571 degree-days (lower temperature threshold, 11.3°C). The predator can feed on all immature stages of the bark beetles O. erosus and Pityogenes calcaratus Eichhoff. However, larvae and adults were recorded gnawing bark, and wood particles were observed inside the alimentary canal. In simulated pine tree systems, adults consumed 0.6–1.9 bark beetle eggs or neonates. The combined effect of adults and larvae suggest that this predator might reduce the population of the bark beetles by up to 90% during spring and autumn and by 30–50% during summer.